Question

What is the equation in the slope-point form of the line that passes through the points (-5,-9) and (7,9) A. y - 9=1.5(x - 5) B. y + 9=1.5(x - 7) C. y - 5=1.5(x + 9) D. y - 9=1.5(x - 7)

Answer 1

D. y - 9 = 1.5(x-7)

Explanation:

First find the slope using this formula. y2-y1/x2-x1

Plug in with (-5, -9) & (7, 9)

9-(-9)/7-(-5) = 18/12 (simplify)

18/12 ÷ 3 = 6/4 ÷ 2 = 3/2

The slope is 3/2 or 1.5

To find the y-intercept plug in one of the points (7, 9)

9 = 3/2(7) + b (b represents the y-intercept)

9 = 10.5 + b

-1.5 = b

The equation is y = 1.5x - 1.5

A. y = 1.5x + 1.5

B. y = 1.5x - 19.5

I'll just skip C the answer is D I'll show the work

y - 9 = 1.5(x-7) (distribute 1.5 to x and -7)

y - 9 = 1.5x - 10.5 (add 9 on both sides)

y = 1.5x - 1.5