Pull out like factors :
-x2 - 2x + 5 = -1 • (x2 + 2x - 5)
Factoring x2 + 2x - 5
The first term is, x2 its coefficient is 1 .
The middle term is, +2x its coefficient is 2 .
The last term, "the constant", is -5
Step-1 : Multiply the coefficient of the first term by the constant 1 • -5 = -5
Step-2 : Find two factors of -5 whose sum equals the coefficient of the middle term, which is 2 .
-5 + 1 = -4
-1 + 5 = 4
Observation : No two such factors can be found !!
-x2 - 2x + 5
