#2**+1 **

Solve for x:

-2 x^2 + 10 x + 25 = 0

Divide both sides by -2:

x^2 - 5 x - 25/2 = 0

Add 25/2 to both sides:

x^2 - 5 x = 25/2

Add 25/4 to both sides:

x^2 - 5 x + 25/4 = 75/4

Write the left hand side as a square:

(x - 5/2)^2 = 75/4

Take the square root of both sides:

x - 5/2 = (5 sqrt(3))/2 or x - 5/2 = -(5 sqrt(3))/2

Add 5/2 to both sides:

x = 5/2 + (5 sqrt(3))/2 or x - 5/2 = -(5 sqrt(3))/2

Add 5/2 to both sides:

**Answer: | x = 5/2 + (5 sqrt(3))/2 or x = 5/2 - (5 sqrt(3))/2**

Guest Apr 11, 2017