Question

Find the missing value so that the two points have a
slope of -
(-2,y) and (0, -4)

Answer 1

y = -2

Explanation:

Use the formula for slope:
`m = (y_(2)-y_(1))/(x_(2)-x_(1))`

"m" means slope, and we know it is -1.

Decide which points will be point 1 and point 2

Point 1 (-2, y) x₁ = -2 y₁ = y

Point 2 (0, -4) x₂ = 0 y₂ - -4

Substitute the "x" and "y" values into the formula

`m = (y_(2)-y_(1))/(x_(2)-x_(1))`

`m = (-4-y)/(0-(-2))` Simplify

`-1 = (-4-y)/(2)` Remember m = -1. Get rid of the fraction

`2*-1 = 2*(-4-y)/(2)` Multiply both sides by 2

`-2 = (2(-4-y))/(2)` The "2"s cancel out on the right

`-2 = -4-y` Start isolating "y"

`-2 +4= -4-y + 4` Add 4 to both sides

`2= -y`

`2/-1= -y/-1` Divide both sides by -1 to isolate "y"

-2 = y Answer

y = -2 Variable on left side