Answer:
15x^2 -26x - 21
Explanation:
We look at the expression and see that we're going to end up multiplying two terms with x together to get a largest factor of x^2, giving us a quadratic equation. A quadratic equation is in standard form when it's of the form ax^2 + bc + c
First, FOIL your terms:
(3x - 7) (5x + 3) = 5x*3x + 3x*3 + -7*5x + -7*3 = 15x^2 + 9x - 35x - 21
Now combine like terms and reorder if necessary:
15x^2 -26x - 21