Explanation:
x²+8x+15
since x² doesn't have coefficient
find two numbers when added will give 8 and when multiplied gives 15
3+5=8
3*5=15
3x and 5x are the numbers
subtitute 3x and 5x with 8x
x²+3x+5x+15
factorize
(x²+3x)(+5x+15)
x(x+3)+5(x+3)
(x+5)(x+3)
NOTE: x=-5 or x=-3 if the formula = 0
Do mark BRAINLIEST