Question

This is factoring trinomials,help plz!

Answer 1

10.
Factor the following:
8 x^2 - 2 x - 10
Factor 2 out of 8 x^2 - 2 x - 10:
2 (4 x^2 - x - 5)

Factor the quadratic 4 x^2 - x - 5. The coefficient of x^2 is 4 and the constant term is -5. The product of 4 and -5 is -20. The factors of -20 which sum to -1 are 4 and -5. So 4 x^2 - x - 5 = 4 x^2 - 5 x + 4 x - 5 = 4 x (x + 1) - 5 (x + 1):
2 4 x (x + 1) - 5 (x + 1)
Factor x + 1 from 4 x (x + 1) - 5 (x + 1):
Answer:  2 (x + 1) (4 x - 5)
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13. 
Factor the following:
16 x^2 - 24 x + 8

Factor 8 out of 16 x^2 - 24 x + 8:
8 (2 x^2 - 3 x + 1)

Factor the quadratic 2 x^2 - 3 x + 1. The coefficient of x^2 is 2 and the constant term is 1. The product of 2 and 1 is 2. The factors of 2 which sum to -3 are -1 and -2. So 2 x^2 - 3 x + 1 = 2 x^2 - 2 x - x + 1 = -(2 x - 1) + x (2 x - 1):
8 x (2 x - 1) - (2 x - 1)

Factor 2 x - 1 from x (2 x - 1) - (2 x - 1):
Answer: 8 (2 x - 1) (x - 1)