85 is composite because it can be divided by 5 and 17
Step-by-step explanation:
I am not sure what exactly you mean.
do you mean the complete square of an expression or
term ?
if so, then by multiplying this term by itself, and that means in general, every part is multiplied by every part and the part results are added considering the signs involved.
e.g.
squaring a+b
(a+b)(a+b) = a×a + a×b + b×a + b×b = a² + 2ab + b²
remember that multiplication and addition are commutative (you can flip the right and left sides with each other and still get the same result : a+b = b+a, a×b = b×a).
squaring a-b
(a-b)(a-b) = a×a + a×-b + -b×a + -b×-b = a² - 2ab + b²
remember that
+×- = -×+ = -
-×- = +
+×+ = +
a more complex example ?
squaring a-b+c
(a-b+c)(a-b+c) =
= a×a + a×-b + a×c + -b×a + -b×-b + -b×c + c×a + c×-b + c×c =
= a² - 2ab - 2bc + 2ac + b² + c²
I think with the kinds of mixture problems, it's really helpful to make a table.
The equations you actually need are

and

. Since I was so close, I went ahead and just solved it anyway. You can see my setup on the attached image.
the answer is C) home loan
(13x6)+89 with the power of 2 is 7999