3 DECK SCRAMBLE Flashcards
what is a coefficient?
the number in front of a variable or variables
f(x) = ax^2 + bx + c What is the coefficient of the linear term?
b
f(x)= 2(x+4)^2-3 What is vertex and which way does it open?
at (-4, -3) and it opens upwards (has min)
why are roots called “zeros”
because it is where the height is zero; where the y value is zero; they are the x values that make the y=0
What is the x intercept of a line? (what are the coordinates?)
Where the line crosses the horizontal axis, the x axis. The coordinates are ( X, 0 )
how do you find “probability”
experimental: (#successes)/(total # tries).
theoretical: (# successful outcomes) / (# total possible outcomes)
When are there no solutions to simultaneous equations?
when the lines don’t cross, when they are parallel (no overlap)
When completing the square and “a” is not equal to 1, what do you have to do?
divide both sides of equation (every term) by that “a” to turn “a” into “1”
f(x)= -2(x-5)^2- 3What is vertex and is it a min or a max? What is the axis of symmetry?
at ( 5, -3) and it is a maximum, the AOS is x=5
what is the constant term’s exponent on the x?
0
How do you get the probability of taking a certain route on a tree diagram?
multiply the branches along the path till the end. write it at the end of the branch.
How can you tell if the point (5, -3) is a solution to a linear equation?
If it “works.” Sub 5 in for the X and -3 in for the Y. Simplify. If the statement is true, then it is a solution. If it is a solution, then it is on the line.
When is there and infinite number of solutions to simultaneous equations?
when they are the same line, then all points on the line satisfy both equations
one out of four is _____ or ____%
0.25 or 25%
three out of five is ____ or ____%
0.6 or 60%
f(x)= 5 - 2x +3x^2 What is a, b and c ?
a = 3, b = -2, c = 5
What are the fractional equivalents of these popular decimals:
0.5 , 0.333, 0.25, 0.2, 0.125, 0.1, 0.01, 0.001
1/2, 1/3, 1/4, 1/5, 1/8, 1/10, 1/100, 1/1000
change the probability of 3/5 to a decimal and a percent
0.6 or 60%
What is the zero product property?
(this)(that)=0 is true when (this)=0 and when (that)=0. this is what we use when solving by factoring.
change the probability 40% to a decimal
0.4
Explain what a parabola with two real roots (real zeros) looks like.
crosses x axis at those roots, at those x values
How do you solve by isolating the x^2 ? (when can you do it?)
When there is no linear term (no x term), simply act like you’re solving for x, but solve for x2 and in the last step, take square root of both sides ( + / - )
change the probability 0.5 to a percent
50%
What do we call b^2-4ac
the discriminant
can you have more than 100% of something?
YES…. if you have more than a whole. (but this can’t be a probability)
what are the decimal equivalents of these popular fractions:
1/2, 1/3, 1/4, 1/5, 1/8, 1/10, 1/100, 1/1000
0.5 , 0.333, 0.25, 0.2, 0.125, 0.1, 0.01, 0.001
change the decimal 0.0003 to a percent
0.03%
What are the roots of a function? (other names?)
the zeros, the x-intercepts, the solutions,where the parabola crosses
f(x) = ax^2 + bx + c What is the constant term?
c (it is the y intercept)
If an x intercept is 455, what point is on the line?
(455, 0)
what does a slope that is undefined look like?
vertical, straight up and down. The y axis has a slope of zero.
why is it called a constant term
alone it would be a constant function.. The same height always. a horizontal line with a constant y, a constant height
What is the standard form of a quadratic?
ax2+bx+c = 0
How many diamonds in a deck of cards?
13
what is the quadratic term’s exponent on the x ?
2
f(x)= 3x^2-6x+3 What is the constant term? what is the y intercept?
3, it is the also the y intercept
Why can’t you divide by zero? (why can zero be in the top and not the bottom?)
10/2 asks “how many times do you add 2 to itself to get to 10?” the answer is 5.
10/0 asks “how many times do you add 0 to istelf to get to 10?” the answer is there is no answer. undefined
where is the vertex located?
on the axis of symmetry (highest or lowest point).
What are the three forms of a quadratic that we use?
standard: y = ax2-bx-c
factored: y = a (x-r) (x-r)
vertex: a (x-h)2 +k
How can you always get rid of fractions in any equation?
Multiply every term by the LCD (plop the LCD in the numerators, then simplify)
What is the gradient of a vertical line?
undefined
change the probability 0.04 to a percent
4%
one out of three is ____ or ____%
about .33 or 33%
how would you solve (3x-2)(x-5)=0 (what are solutions?)
set factors = 0 and solve: 3x-2=0 and solve x-5=0 zero product property. The solutions are x = { 5, 2/3}
what is tricky about the vertex form?
the -h part.. If its (x+9)2 +8 then h is -9.. remember that x=h is also the AOS !!!
What if you solve simultaneous equations all three ways, what will you notice?
they all give the same answer, the same POINT, (x,y)
If the discriminant is zero, what do you know about roots?
there is one double root, it is a perfect square, the parabola just touches down x axis without crossing, the vertex is on the x axis.
if there are 10 kids and you are choosing 3 to bring on a trip, how many ways can you do that? (perm or comb?)
Combination. nCr with n=10 and r=3
How do you show that a point lies on a line?
Show that, when you plug the point in, you get a true mathematical statement.
What are the solutions of a function? (other names)
the roots, the x intercepts, the zeros where the parabola crosses
How do you find the vertex of a parabola in standard form? y=ax^2+bx+c
the x value is always -b/2a . To get the y value for it, put that x value into the function and solve
what is the tough thing about quadratics?
the fact that they are squared.. We have to undo that x2. We want to get it linear!!
What does (A’)’ look like when shading?
double negative. (A’)’ = A, so the entire A circle should be shaded.
What is the x coordinate for all y-intercepts?
zero. all y intercepts are in the middle, not left or right, because they are on the y axis.
How do you solve by factoring?
get stuff all on one side, factor, set each factor = 0, solve each linear equation.
f(x) = a(x-h)^2 + k where it the vertex? what is the Axis of Symmetry?
vertex at the point (h, k), the AOS is the vertical line x= h
When you shade a VENN diagram, what does A U B look like?
Both circles and the overlap are all shaded (everything inside)
Perpendicular lines have _____ gradients, or slopes
OPPOSITE SIGN AND RECIPROCAL
How do you convert from vertex to standard form?
square the binomial and combine stuff
What does the discriminant tell us about?
about the roots, the zeros, how many x intercepts the parabola has, how many times it crosses the x axis, whether roots are real or imaginary
change the probability of 2/3 to a decimal and a percent
about .67 or 67% (.66666666666)
What is the “general” form of a line?
Ax + By = C no fractions.
what is the “most popular” form of a line?
gradient intercept (slope intercept)
What does the quadratic formula say about finding the x intercepts? (stand where and do what?)
stand at the AOS and reach up and down a bit to find the solutions
Geometrically, how is the shape of a parabola made?
A parabola is the set of all points equidistant from point, called the focus, and a line, called the directrix.
How many kings in a deck of cards?
4
Describe what an axis of symmetry is
it is where the parabola can fold onto itself. It is the equation of this vertical line, so you write “x = ___”(-b/2a)
f(x) = a(x-h)^2 + k How do we know if it opens up or down?
by the sign of a, if its positive, up, negative , down
what is the slope of a line that goes straight up and down?
undefined
when you are given a two way table, what should you always do?
PUT IN THE TOTALS ON SIDE and BOTTOM and the OVERALL TOTAL IN THE CORNER
what is the probability of getting 3 tails in a row flipping a coin?
1/2 x 1/2 x 1/2 = 1/8
one out of ten is _____ or ____%
0.1 or 10%
What are the zeros of y=5(x-3)(2x+1)
The zeros, or roots, or x intercepts are at(3, 0) and (-1/2, 0)
What is the discriminant?
b2-4ac (notice there is no sq root on it!!)
If the discriminant is zero, how many times does the parabola hit the x axis?
- hits it and bounces off.
How is the axis of symmetry hidden in the quadratic formula?
it is the beginning.. (put both parts over 2a).. -b/2a
What is the quadratic formula?
x = -b +- sqroot b squared - 4ac all over 2a (but in formula)
f(x)= 3x^2-6x+3 What is the coefficient of the linear term?
-6 this is also known as “b”
What is the gradient-intercept form?
y = mx + c
f(x)= 3x^2-6x+3 What is the linear term?
-6x
what is the linear term’s exponent on the x ?
1
change the probability of 1/4 to a decimal and a percent
0.25 or 25%
What is the gradient of a horizontal line?
ZERO
How do you solve simultaneous equations by substitution?
isolate a variable. SUBSTITUTE into the other equation, solve, then sub back in to find (x,y)
What is the symbol that joins two sets together into one set?
A big U , stands for UNION
how can you think of 150% of something?
150% of a pizza is one and a half pizzas!! (this can’t be a probability)
What numbers can represent a probability?
Always between 0 and 1, examples: 0, .75, .05, 1, .35
change the decimal 0.03 to a fraction
3/100
f(x)= -4x^2 + 8 What is a, b and c ?
a = -4, b = 0, c = 8
What does A’ mean?
The elements not in A
how would you solve 4x^2 - 9 = 13 ? (just say what you’d do)
no linear term, so just isolate the x2 and root sides
What is the probability of randomly taking one card and getting a diamond from a deck?
13/52 or 1/4
f(x) = ax^2 + bx + c What is the coefficient of the constant term?
c (it is the y intercept)
change the decimal 0.0003 to a fraction
3/10000
What is the y intercept of a line? (what are the coordinates?)
Where the line crosses the vertical axis, the y axis. The coordinates are ( 0, Y )
What is a midpoint?
the point halfway along a segment. right in the MIDDLE
f(x)= -4x^2 + 8 What is the axis of symmetry?
x= -b/2a = -0/2(-4) = 0/8 = 0. AOS is x=0, which is the y axis!!
change the probability of 1/3 to a decimal and a percent
about .33 or 33% (.33333333333)
If the discriminant is negative, what do you know about roots?
there are no real roots, 2 imaginary roots, the parabola doesn’t touch x axis
change the probability of 1/2 to a decimal and a percent
0.5 or 50%
How do you find the midpoint between two given points?
the midpoint has an x and y value, (x,y). the X value is the average of the two x values, and the Y value is the average of the two y values.
change the probability of 2/5 to a decimal and a percent
0.4 or 40%
How would you solve 9x^2 - 3x = 0 ? (just say what you’d do)
factor out x and set factors=0.. (one solution will be 0)
What is a perpendicular bisector?
the line that goes through the midpoint of a segment, and it is also perpendicular to it.
Explain what the graph of a parabola with no real roots (real zeros) looks like.
doesn’t touch x axis
If a line as a slope of -5, then any line parallel to it will have a slope of ___ and any line perpendicular to it will have a slope of ___
-5 and perp 1/5
why is it called a discriminant?
because it discriminates between which type of solutions, roots and zeros you will have (2real, one real or imaginary)
What are the zeros of a function? (other names?)
the roots, the x intercepts, the solutions, where the parabola crosses
When is there just one solution to simultaneous equations?
when they cross (at one point)
How can you think of %
PER 100 (or, divided by 100)
What are the five ways to solve a quadratic?
set to zero and factor, complete square, quadratic formula, graph and look for x-intercepts, or when there is no linear term, isolate the x2 and root both sides.
What is the graph of a line showing us? (or a graph of a parabola or any function)
It is showing us all of the points, (x,y), that make the equation true. Every dot on the graphed line will make the equation true, they all work.
What is the slope of a line in standard (general) form?
-A/B