Question

If (x+1)(x+3)=5, then which of the following statements iis true? (X+11)=0 or x-3=0, x+1=5 or x-3=5, x-4=0 or x+2=0

Answer 1

Explanation:

Multiplying out (x+1)(x+3)=5, we get x^2 + 3x + 1x + 3 = 5, or

x^2 + 4x = 2, or

x^2 + 4x - 2 = 0

The solutions of this quadratic are:

-4 ± √( 16 - 4(1)(-2) ) -4 ± √8

x = ----------------------------- = -------------

2 1

Both roots have the component √2 in them, and so none of the possible answer choices matches. Double check, please, to ensure that you've copied this problem down correctly. Thx.

x = -----------------