Hey there!!
We have:
... 10x² - 14xy - 15x + 21y
Now, let's group these terms.
... 10x² - 15x - 14xy + 21y
Now, we have grouped these terms. We have two sections.
10x²-15x and -14xy+21y
Now, let's take common term in both these sections.
... 10x²-15x (The common term is 5x )
Hence, this would become:
... 5x(2x-3)
And -14xy + 21y
(The common term,is 7y )
... 7y(-2x+3)
Hence, the equation would be :
... 5x(2x-3)+7y(-2x+3)
... (5x+7y)(2x-3)
Hence, a = x and ?=7
Hope my answer helps!
