(x - 6)(x - 7)
x-4 is the correct answer for Apex
x(x2 + 36)
You should look for two numbers whose product is 40, and whose sum is 13. Experimenting a little (trying different pairs of factors for 40), you can quickly realize that this works for 8 and 5. Therefore, x2 + 13x + 40 = (x + 8) (x + 5)
x - 4. x^2 + 5x - 36 = (x - 4) (x + 9) x^2 - 9x + 20 = (x - 4) (x - 5)
x2 + 13x + 36 = (x + 9)(x + 4)
(x-4)
vbh
x2 + 13x + 36 = 0 so (x+4)(x+9) = 0 so that x = -4 or x = -9
x2-13x+36=(x-9)(x-4)=0 x=9 or x=4
(x - 9)(x - 4)
(x -3)(2x2 + 3x - 4)
(x + 10)(x + 3)
(x - 10)(x - 3)
x2 + 13x + 40 = x2 + 5x + 8x + 40 = x(x + 5) + 8(x + 5) = (x + 8)(x + 5)
x2 + 13x + 12 = (x + 1)(x + 12)
(x - 5)(x - 8)