Question

factoring perfect square trinomials and differences of squares...factor completely, remember to look 1st for a common factor. check by multiplying. if it is a prime state it. 9x^2+30x+25

Answer 1

9x^2+30x+25
= 9x^2 + 15x + 15x + 25
= 3x(3x + 5) +5(3x + 5)
= (3x + 5)(3x + 5)

Answer 2

how do i check my answer by multiplying? Is it a prime? How do you know if it is a prime or not?

Answer 3

We can also solve it using the identity a^2 + 2ab + b^2 = (a + b)^2

9x^2+30x+25
= (3x)^2 + 2(3x)(5)+ (5)^2
using the identity a^2 + 2ab + b^2 = (a + b)^2
= (3x + 5)^2

so 9x^2+30x+25 = (3x + 5)^2
or
9x^2+30x+25 = (3x = 5)(3x + 5)

Answer 4

Prime factor is a factor from which nothing more can be taken out as common

suppose we get something like (3x - 9)
It is not prime as we can take out 3 as common factor i.e. 3(x - 3)

In above case we have got both factors as 3x + 5
there is nothing common between 3x and 5.........
so they r prime factors

Answer 5

so to check my answer i would multiply the final equation, correct?
3x*3x=9x^2
3x*5=15x
5*3x=15x
5*5=25
combine like terms- 15x/15x=30x
9x^2+30x+25

Answer 6

Yes that is correct.....

Answer 7

what is the greates common factor? Is it 3?