Question

supply missing term to make expression a perfect trinomial. 9f^2- ___+25

Answer 1

30x

Answer 2

How do you do this?

Answer 3

notice that 9f^2 = (3f)^2
and 25 = 5^2
from the formula (a-b)^2 we know that
(a-b)^2 = a^2 - 2ab + b^2

Answer 4

im still not 100% on it.

Answer 5

9f^2- ___+25 = (3f)^2 - ____+5^2
to make this into a perfect trinomial, you need to complete the square.
which is what I did using the formula (a-b)^2
where a = 3f and b = 5

Answer 6

so you subtract 9f^2 and -4 and get 5 and add 25. Wouldnt it be 30f^2?

Answer 7

what is (3f-5)^2?
expand it and post the answer.

Answer 8

-2f^2=-4f

Answer 9

what?
do you know the formula for (a-b)^2