Kevin’s Cards about 7th and 8th Grade Math Flashcards
What is the solution to a linear equation in 2 variables
A solution to a linear equation in 2 variables is a point: (x,y) or ordered pair
How many solutions does a linear equation in two variables have
Linear equations in 2 variables have infinitely many solutions and each solution is a point that lies on the same line as all the other solutions
Ax + By = C is what equation
Ax + By = C is a linear equation in 2 variables
How do you find the solution to linear equations with 2 variables
To find solutions to linear equations, chose a value for x, substitute the value into the equation , and solve for y. Do the same thing to solve for x with y
What is the standard form of a linear equation
The standard form of a linear equation is: Ax + By = C, where A,B, and C are integers, A is positive and B is non-zero
What is the names of the point of where a line crosses the x-axis and y-axis
The x-intercept of a graph is the x-coordinate of the point where the line intersects the x-axis. The y-intercept is the y-coordinate of the point where the graph intersects the y-axis
What is a Proportional Relationship
Proportional Relationships are a special type of linear equation when the ratio between two quantities is constant, the quantities have a proportional relationship
Rate Definition
A ratio of two quantities measured in different units
In a proportional relationship between two variables increases at a constant what
In a proportional relationship between two variables increases at a constant rate (also called a unit rate) as the other variable increases by one
Ratio Definition
A comparison of two quantities by division
A proportional relationship can be modeled as what
y = mx
When is the slope (m) on a graph positive
The slope (m) is positive if the line rises from left to right
When is the slope (m) on a graph negative
The slope (m) is negative if the line falls from left to right
What is the slope (m) on a graph equal to 0
The slope (m)is equal to 0 when the line is horizontal
What is a slope
The slope of a line is the ratio of the vertical change between any two point on the line to the horizontal change
What is another name for the vertical change and the horizontal change of a line’s slope
The vertical change is called the rise and the horizontal change is call the run
What is the format for the equation for slope
Vertical change/ Horizontal change or Rise/ Run
What directions do you move when moving in a positive or negative direction on a graph
When you move up or right you move in a positive direction. When you move down or left, you move in a negative direction
What is the Formula for Slope
y2 - y1/ x2 - x1
What is the slope of a vertical line on a graph
A slope is undefined if the line is vertical
What is a hypotenuse
The hypotenuse of a right triangle is the longest side of the triangle which is always opposite of the right angle (90 degrees)
Any two points on a line are what
Any two points on a line are the end points of a segment that, together with the rise and run, form a right triangle
What can the slope of the line tell you about the rate
The greater the slope of the line, the greater the rate. So when you compare lines, the line with the greater slope has the greater rate
What does the steepness of a line on a graph tell you
The steeper the line, the greater the slope
Each form of a linear equation communicates what
Each form quickly communicates specific information
What is the point - slope form of a line useful for
Communicating the slope of a line and one-point on the line
What is Point Slope Form
y - y1 = m(x - x1)
If a number is added in point-slope form what sign is it
It is negative
A proportional relationship can be modeled as what
y = mx
When a graph intersects the origin, you can do what to find the slope
Use any point to find the slope
What is slope-intercept form
y = mx + b, where b the y-intercept and m is the slope
Rate Definition
A ratio that compares quantities of a different kinds of units
Unit Rate Definition
A rate in which the 2nd quantity is 1
Terminating Decimals Definition
Decimals that have a finite number of nonzero digits
Initial Value Definition
The beginning value of a linear relationship; y-intercept
Ratio Definition
The relationship between two or more quantities
Mph is and example of what
An unit rate
Two or more linear equations using the same variables make up what
A system of linear equations
What is the solution of a system of linear equations
A solution of a system of linear equations is a point where the lines of the equations intersect
What does percent mean
Per 100
How do you convert a fraction to a percent
Multiply by 100
How do you convert a percent to a fraction
Divide by 100
A system with at least one solution is a what
A consistent system
What is a system with exactly one solution called
A consistent independent system
The lines in a consistent independent system do what
They intersect at exactly one point and have different slopes
A system with infinitely many solutions is what
A consistent dependent or a coincident
The lines in a consistent dependent system is also called a what
Coincident