Question

Factor the trinomial: 4x2 - 8x - 5
A. (2x + 1)(2x - 5)
B. (4x + 1)(x - 5)
C. (4x - 5)(x + 1)
D. prime

Answer 1

Correct answer is A.

$(2x + 1)(2x - 5) \\2x(2x-5)+1(2x-5) \\4x^2-10x+2x-5 \\4x^2-x-5$

Answer 2

you can always check by expanding the answers to see what matches

well, you can verify yourself by expanding the answer to check what matches

4x2 - 8x - 5 = 4x2 + 2x -10x -5
= 2x(2x+1) - 5(2x+1)
= (2x+1)(2x-5)