Answer:
x = 3/4 + (3 sqrt(5))/4 or x = 3/4 - (3 sqrt(5))/4
Explanation:
Solve for x over the real numbers:
8 x^2 - 12 x - 23 = -5
Divide both sides by 8:
x^2 - (3 x)/2 - 23/8 = -5/8
Add 23/8 to both sides:
x^2 - (3 x)/2 = 9/4
Add 9/16 to both sides:
x^2 - (3 x)/2 + 9/16 = 45/16
Write the left hand side as a square:
(x - 3/4)^2 = 45/16
Take the square root of both sides:
x - 3/4 = (3 sqrt(5))/4 or x - 3/4 = -(3 sqrt(5))/4
Add 3/4 to both sides:
x = 3/4 + (3 sqrt(5))/4 or x - 3/4 = -(3 sqrt(5))/4
Add 3/4 to both sides:
Answer: x = 3/4 + (3 sqrt(5))/4 or x = 3/4 - (3 sqrt(5))/4