Question

Factor each for the differences of two squares

Answer 1

do you mean x<2=4x+21?

Answer 2

(x+3).(x-7)=0->x=7 and x=-3

Answer 3

-7 and 3

Answer 4

Thanks. How exactly would I know how to solve? Is there a way or method that would help me to remember?

Answer 5

Would I factor then, find the sum?

Answer 6

-21=-7.3 and 7-3=-(-4)

Answer 7

Oh okay. So it's similar to the trial and error method. Thanks

Answer 8

\[x1,2 =( -b \pm \sqrt{b^2 -4ac})/2a\], where a=-1, b=4, c=21

Answer 9

or you could use the sum product method as product of the 2 terms = 21 and sum of the two terms =-4.

Answer 10

sum of two therms is 4 not -4