Question

Use the quadratic formula to find the solutions to the quadratic equation below. Check all that apply

4x^2-x-5=0

Answer 1

4x^2+4x-5x-5=0

4x(x+1)-5(x+1)=0

(x+1)=0. 4x-5=0

x=-1

x=5/4

Answer 2

D. 5/4

F. -1

Explanation:

The quadratic formula x =
`(-b +/- √(b^2 - 4ac) )/(2a)`

The given equation is 4x^2 - x -5 = 0

Here a = 4, b = -1, and c = -5.

Plug in these values into the formula.

x =
`(-(-1) +/- √((-1)^2 - 4*4*-5) )/(2*4)`

x=
`(1 +/- √(1 + 80) )/(8)`

x = (1+/- 9)/8

x = (1+9)/8 and x = (1 -9)/8

x = 10/8 and x = -8/8

x = 5/4 and x = -1

The answers are

D. 5/4

F. -1

Hope this will helpful.

Thank you!