Pearson Algebra 2 Common Core, 2011
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Pearson Algebra 2 Common Core, 2011 View details
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Exercise 6 Page 191

Start by graphing the line, then use the Slope Formula to find its slope.

Equation: y=1/2x+8
Graph:

Practice makes perfect

First let's graph the given points and connect them with a line.

Now we will write the equation in slope-intercept form. y= mx+b For an equation in this form, m is the slope and b is the y-intercept. Let's use the given points to calculate m. We will start by substituting the points into the Slope Formula.
m=y_2-y_1/x_2-x_1
m=11- 9/6- 2
Simplify right-hand side
m=2/4
m= 1/2
A slope of 12 means that for every 2 horizontal steps in the positive direction, we take 1 vertical step in the positive direction. Now that we know the slope, we can write a partial version of the equation. y= 1/2 x+b To complete the equation, we also need to determine the y-intercept b. Since we know that the given points will satisfy the equation, we can substitute one of them into the equation to solve for b. Let's use ( 2, 9).
y=1/2x+b
9=1/2( 2)+b
Solve for b
9=1+b
8=b
b=8
A y-intercept of 8 means that the line crosses the y-axis at the point (0,8). We can now complete the equation. y= 1/2x+(8)