Answer:
The first term is, x2 its coefficient is 1 .
The middle term is, +5x its coefficient is 5 .
The last term, "the constant", is +21
Step-1 : Multiply the coefficient of the first term by the constant 1 • 21 = 21
Step-2 : Find two factors of 21 whose sum equals the coefficient of the middle term, which is 5 .
-21 + -1 = -22 -7 + -3 = -10 -3 + -7 = -10 -1 + -21 = -22 1 + 21 = 22 3 + 7 = 10 7 + 3 = 10 21 + 1 = 22