Question

Use the quadratic formula to solve the following quadratic equation: 8x2 + 2x - 3 = 0.



A. x = -7/8 or 3/8
B. x = -11/8 or 9/8
C. x = -3/4 or 1/2
D. x = -1/2 or 3/4

Answer 1

It's in the form ax² + bx + c = 0, so a = 8, b = 2, c = -3

The quadratic equation is

x = (-b ± √(b² - 4ac))/(2a)

So you have

x = (-2 ± √(2² - 4*8*(-3)))/(2*8) = (-2 ± √(4 + 96))/16 = (-2 ± √100)/16 = (-2 ± 10)/16

If it's +, you have 8/16 = 1/2

If it's -, you have -12/16 = -3/4

The answer is -3/4 or 1/2, so it's C

Answer 2

Thank you

Answer 3

You're welcome! Do you understand it?