Question

4b^2-4b=-1

A)0
B)1
C)2
D)3

Answer 1

B

Explanation:

Took the test. Answer is 1/2.

Answer 2

Explanation:

Take out 4 from each term on the left.

4(B^2 - B) = -1 Divide both sides by 4

4(B^2 - B)/4 = - 1/4

(B^2 - B) = -1/4 Add 1/4 to both sides

B^2 - B + 1/4 = - 1/4+1/4

B^2 - B + 1/4 = 0

(b - 1/2)(b - 1/2)

This has 2 equal roots of (b - 1/2)(b - 1/2) or b = 1/2 , b = 1/2.

When that happens, the quadratic just touches the x axis (in this case at 1/2)

I've provided a graph to show you how this happens. None of your choices are what I'm getting. The answer is 1/2 no matter how it is factored.