The linear equation for line (1) on the above graph is:
A) y = 8 + 2x
B) y = 8 + .5x
C) x = 8 + .5y
D) y = 8 - 2x

Question

The linear equation for line (1) on the above graph is:
A) y = 8 + 2x 
B) y = 8 + .5x 
C) x = 8 + .5y 
D) y = 8 - 2x

Quizplus · Accepted Answer

The line (1) passes through the point (8, 12) and (18, 17). Using the slope-intercept form of a linear equation, we can find the equation of the line:
y - y1 = m(x - x1)
where m is the slope and (x1, y1) is any point on the line. 
m = (17 - 12) / (18 - 8) = 0.5
Now substituting (8, 12) into the equation and simplifying:
y - 12 = 0.5(x - 8)
y = 0.5x + 8
So, the linear equation for line (1) is y = 8 + .5x, which is answer choice B.

The Linear Equation for Line (1) on the Above Graph