Let the two numbers be x and y
then x+y=9
x-y=3
2x=12
x=6
6+y=9
y=3
so the numbers are 9 and 3
I believe it is 84. good luck.
General formula to make slope-intercept form
y - y₁ = m(x - x₁)
From the question, we know that
m = 3/4
(x₁,y₁) = (-8,3)
Put the number to the formula
y - y₁ = m(x - x₁)
y - 3 = 3/4(x - (-8))
y - 3 = 3/4(x + 8)
y - 3 = (3/4)x + 6
y = (3/4)x + 9