Answer:
[tex]\boxed{(7-5x)(49+35x+25x^2)}[/tex]
Step-by-step explanation:
These are the steps you must follow to solve this problem:
Step 1:
We can write [tex]125=5^3[/tex] and [tex]343=7^3[/tex] so:
[tex]343-125x^3=(7^3-5^3x^3)[/tex]
Step 2:
We can arrange this as follows:
[tex]343-125x^3=[7^3-(5x)^3][/tex]
Step 3:
So we can use difference of cubes formula:
[tex](a^3-b^3)=(a-b)(a^2+ab+b^2)[/tex]
So:
[tex]a=7 \\ \\ b=5x[/tex]
Therefore:
[tex]343-125x^3=(7-5x)[(7)^2+(7)(5x)+(5x)^2][/tex]
[tex]343-125x^3=(7-5x)(49+35x+25x^2)[/tex]
