Question

Find the value of this expression if x = 4 x^2 -8

Answer 1

Let's solve your equation step-by-step.

x=4x2−8

Step 1: Subtract 4x^2-8 from both sides.

x−(4x2−8)=4x2−8−(4x2−8)

−4x2+x+8=0

For this equation: a=-4, b=1, c=8

−4x2+1x+8=0

Step 2: Use quadratic formula with a=-4, b=1, c=8.

x=−b±√b2−4ac2a

x=−(1)±√(1)2−4(−4)(8)2(−4)

x=−1±√129−8

x=18+−18√129 or x=18+18√129

Answer:

x=18+−18√129 or x=18+18√129