Question

Find the value of y so that the points (-5,10) and (3,y) lie on a line with slope -3/8.

Answer 1

Answer:

y = 7

Step-by-step explanation:

calculate the slope m using the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (- 5, 10) and (x₂, y₂ ) = (3, y)

m = $\frac{y-10}{3+5}$ = $\frac{y-10}{8}$

For this to equal - $\frac{3}{8}$

since the denominators are equal, equate the numerators

y - 10 = - 3 ( add 10 to both sides )

y = 7