Hellllp please! I need to solve for y if x=-2 Here is the equation: x=2y^2-4y-5
Solve for y:
-2 = 2 y^2-4 y-5
-2 = 2 y^2-4 y-5 is equivalent to 2 y^2-4 y-5 = -2:
2 y^2-4 y-5 = -2
Divide both sides by 2:
y^2-2 y-5/2 = -1
Add 5/2 to both sides:
y^2-2 y = 3/2
Add 1 to both sides:
y^2-2 y+1 = 5/2
Write the left hand side as a square:
(y-1)^2 = 5/2
Take the square root of both sides:
y-1 = sqrt(5/2) or y-1 = -sqrt(5/2)
Add 1 to both sides:
y = 1+sqrt(5/2) or y-1 = -sqrt(5/2)
Add 1 to both sides:
Answer: |y = 1+sqrt(5/2) or y = 1-sqrt(5/2)
