Answer:
(5x²+3)(2x-7)
Explanation:
As stated, this is a factor by grouping question: a(x+y)+b(x+y)=(x+y)(a+b)
10x³-35x²+6x-21
first, look for common factors.
-35x² and -21 have the common factor of -7
10x³and 6x have the common factor of 2x
now, rearrange the polynomial
10x³+6x-35x²-21
factor 2x out of 10x³+6x
2x(5x²+3)
factor -7 out of -35x² and -21
-7(5x²+3)
Now, the polynomial is 2x(5x²+3)-7(5x²+3)
(5x²+3) is common in both parts, so factor that out, 2x-7 would be another expression as that is left.
now, the expression is
(5x²+3)(2x-7)
Hope this helps!