Mathematics 3 Flashcards
what is the formula for the axis of symmetry of a parabola?
x = -b/2a
What is step one of solving a quadratic equation by completing the square?
express as x squared + px = q
What is step two of solving a quadratic equation by completing the square?
Add the square of half the coefficient of x to both sides
What is step three of solving a quadratic equation by completing the square?
Replace the perfect trinomial square by its binomial squared
What is step four of solving a quadratic equation by completing the square?
Take the square root of both sides
Don’t forget square roots can usually be positive or negative
What is the quadratic formula?
x = -b +- sqroot of b2 - 4ac all over 2a
Every quadratic equation has two roots.
If the product of two factors is zero, then one or the other factors or both must equal zero.
What is a reciprocal of a number?
1 divided by the number
Rule 1 of Reciprocals
The fractions a/b and b/a are reciprocals of each other, that is, the reciprocal of a fraction is the fraction inverted
Rule 2 of Reciprocals
The product of two reciprocals is 1
Rule 3 of reciprocals
To divide by a number or a fraction, multiply by it’s reciprocal
Rule 4 of Reciprocals
To solve an equation for an unknown having a fractional coefficient, multiply both members by the reciprocal fraction.
Thus if 2/3x = 10 multiply both sides by 3/2. x = 30/2 x = 15
If a fraction means division, what does 3/4 mean?
3 divided by 4
The numerator is the dividend and the denominator is the divisor.
If x and y vary inversely as each other, and a value of either x or y is multiplied by a number, then the corresponding value of the other is ________ by the same number.
Divided
If the length of a rectangle is doubled and the width is halved, its area _______.
Remains constant