Question

What is the slope-intercept form of the equation of the line graphed in the figure?

A. y = 5⁄3x + 1
B. y = –5⁄3x – 1
C. y = –3⁄5x + 1
D. y = 3⁄5x + 1

Answer 1

D

Explanation:

It crosses the y-axis at y=1 so the y-intercept is b=1.

The slope is count straight up from (-5,-2) to you are on the same horizontal level as (5,4). The rise is 6

Once you get the same horizontal level as (5,4), you will count straight over to you get to (5,4). The run is 10.

Slope=rise/run=6/10=3/5.

Or you could find slope by using the slope formula. I like to line up two pairs of points and subtract then put 2nd difference over first difference. Like so,

(5,4)

-(-5,-2)

----------

10 6

So the slope is 6/10 or 3/5 after reducing.

Slope-intercept form of a line is y=mx+b

Plug in m=3/5 and b=1

y=3/5 x +1

So the answer is D.