Choose the equation that represents the graph below: a. y = x − 3 b. y = −x + 3 c. y = −x − 3 d. y = x + 3

y = x+3 which is choice D



Explanation:

This graph goes through (0,3) and (2,5). You can pick any two points on the diagonal line.

Slope:
m = (y2-y1)/(x2-x1)
m = (5-3)/(2-0)
m = 2/2
m = 1

The y intercept is b = 3 as the point (0,3) is on the line

Therefore, 
y = mx+b
turns into
y = 1x+3
which is the same as 
y = x+3

Note how plugging in something like x = 4 leads to
y = x+3
y = 4+3
y = 7
and we can see on the given graph that (4,7) is a point on the diagonal line. So this helps confirm we have the proper answer

The scale factor of what ?