(10x - 1)^2
Does it = 100x + 1
Memorizing the following identities will help you with similar problems:
(a+b)^2=a^2+2ab+b^2
(a-b)^2=a^2-2ab+b^2
Now put a=10x, b=1 and apply to (a-b)^2
(10x - 1)^2
=(10x)^2 -2(10x*))+(1)^2
=100x²-20x+1
Does it = 100x + 1
(a+b)^2=a^2+2ab+b^2
(a-b)^2=a^2-2ab+b^2
Now put a=10x, b=1 and apply to (a-b)^2
(10x - 1)^2
=(10x)^2 -2(10x*))+(1)^2
=100x²-20x+1