McGraw Hill Glencoe Algebra 2, 2012
MH
McGraw Hill Glencoe Algebra 2, 2012 View details
Mid-Chapter Quiz
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Exercise 12 Page 91

Substitute 0 and solve for a variable twice before graphing.

x-intercept: (-3,0)
y-intercept: (0,4)

Practice makes perfect

We will find the x- and y-intercepts first. Then we will graph the given equation by plotting and connecting them with a line.

Finding the x-intercept

Think of the point where the graph of an equation crosses the x-axis. The y-value of that ( x, y) coordinate pair is 0 and the x-value is the x-intercept. To find the x-intercept of the given equation, we will substitute 0 for y and solve for x.

4x-3y+12=0
4x-3( 0)+12=0
4x+12=0
4x=-12
x=- 3
An x-intercept of -3 means that the graph passes through the x-axis at the point ( - 3,0).

Finding the y-intercept

Let's use the same concept to find the y-intercept. Consider the point where the graph of the equation crosses the y-axis. The x-value of the ( x, y) coordinate pair at the y-intercept is 0. Therefore, substituting 0 for x will give us the y-intercept.

4x-3y-12=0
4( 0)-3y-12=0
-3y-12=0
- 3y=- 12
y=4

A y-intercept of 4 means that the graph passes through the y-axis at the point (0, 4).

Graphing the Equation

We can now graph the equation by plotting the intercepts and connecting them with a line.