Answer:
(x + 1)(x - 7) is the odd one.
Explanation:
1) sum= 8
Product = 7
Factors = 1 , 7 {1*7 = 7 & 1+7 = 8}
x² + 8x + 7 = x² + x + 7x + 7
= x(x + 1) + 7(x + 1)
=(x +1 )(x + 7)
2) x² - 8x + 7 = x² -x -7x + (-1)*(-7)
= x(x - 1) - 7(x - 1)
=(x - 1)( x - 7)
3)Sum = 6
Product = -7
Factors = (-1) , 7 { -1 + 7 = 6 & (-1)*7 = -7}
x² + 6x - 7 = x² - x + 7x - 7
= x(x - 1) + 7(x - 1)
= (x - 1)(x + 7)