Question

Y=4x^2+x-1 solve using quadratic formula

Answer 1

Answer:

x = sqrt(17)/8 - 1/8 or x = -1/8 - sqrt(17)/8

Step-by-step explanation using the quadratic formula:

Solve for x over the real numbers:

4 x^2 + x - 1 = 0

Divide both sides by 4:

x^2 + x/4 - 1/4 = 0

Add 1/4 to both sides:

x^2 + x/4 = 1/4

Add 1/64 to both sides:

x^2 + x/4 + 1/64 = 17/64

Write the left hand side as a square:

(x + 1/8)^2 = 17/64

Take the square root of both sides:

x + 1/8 = sqrt(17)/8 or x + 1/8 = -sqrt(17)/8

Subtract 1/8 from both sides:

x = sqrt(17)/8 - 1/8 or x + 1/8 = -sqrt(17)/8

Subtract 1/8 from both sides:

Answer: x = sqrt(17)/8 - 1/8 or x = -1/8 - sqrt(17)/8