Factorize
a)a²x+2ax-3x+5a²+10a-15
b)(a+b)(a-b)-a+b
c)x³-x²+x+x²y-xy+y​

(a)x(a^2+2a-3)+5(a^2+2a-3)

21 + 12i

step-by-step explanation:

heres step by step

presumably all methods would give the same solution; for each choice we just try x=-4, y=2 and see if it checks.

a.

3x+13y=3(-4)+13(2)=-12 + 26 = 14   that checks

6x+11y=6(-4)+11(2)=-24 + 22 = -2 that checks too

b.  

4x + 5y =4(-4)+5(2)=-16 + 10 = 6   nope

c.

5x+4y = 5(-4)+4(2)=-20 + 8= -12 nope

d.

10x+3y = 10(-4)+3(2)=-40 + 6 = -34 nope

answer: a (the first one) is correct