Question

factor by grouping what is 3x²-9x-8x+24

Answer 1

Look at the first two terms, and take out a common factor. In this case, 3x. So the first two terms become 3x(x-3). Now, the (x-3) will always reappear in the part as well. What I mean is, it will be 3x(x-3)___(x-3). With a coefficent filling in the blank spot, and to figure out that coefficient just figure out what you need to multiply (x-3) to get back to the latter two terms of the original which is -8x+24. So clearly, the coefficient in the blank is -8. So you have 3x(x-3)-8(x-3), which factors into (x-3)(3x-8)