2x to the 2nd power + 7x -15
is the same as:
2x^2 + 7x - 15
This can then be factorised to become:
(2x - 3)(x + 5)
You can then check that this is correct by multiplying out the brackets:
(2x - 3)(x + 5) = 2x^2 + 10x - 3x - 15 = 2x^2 + 7x - 15
which is correct. 