simplify (5x-4)^2

Question

I got 25x^2 -16

is that right?

Answer 1

If you worked according to the FOIL rule, you would expect 4 terms, which simplify to 3 in this case.

A standard identity for the square of a binomial is as follows:

(a+b)²
=a²+2ab+b²
so
(5x)²= 25x²
2(5x)(-4)=-40x
(-4)²=+16

So altogether:
(5x-4)²=25x²-40x+16

Answer 2

okay thanks :)

Answer 3

how to solve .25x + 2 = 12

Answer 4

.25x+2=12
-2 -2
------------
.25x=10
--------
.25 .25

x=40