Answer:
(3x²+4y)(3x²-4y)
Step-by-step explanation:
"difference in two squares" is the formula where a²-b²=(a-b)(a+b)
So we need to apply that formula to [tex]9x^{4}[/tex]-16y², where [tex]9x^{4}[/tex] is a and 16y² is b
First, we need to find the two factors, when squared, equal [tex]9x^{4}[/tex] and 16y²
let's start with [tex]9x^{4}[/tex]
9 is 3 squared; [tex]x^{4}[/tex] is x² squared
let's try 3x² as a factor
To double check, we can square it
(3x²)²
apply the Laws of Exponents; square 3 and multiply the power by 2
when you solve, the answer will be [tex]9x^{4}[/tex]
So it works
now let's find the factor for 16y²
16 is 4 squared, and y² is y squared
so let's try 4y
(4y)²
apply the Laws of Exponents; square 4 and multiply the power by 2
the result is 16y²
Also works!
Now let's apply the formula; as said above, [tex]9x^{4}[/tex] is a and 16y² is b
so: [tex]9x^{4}[/tex]-16y²=(3x²+4y)(3x²-4y)
we can even double check this:
multiply the 2 binomials; apply FOIL
[tex]9x^{4}[/tex]-12x²y+12x²y-16y²
the 2 12x²y's cancel out
and the result is
[tex]9x^{4}[/tex]-16y²
Hope this helps!