Question

Please help me solve this, non spam answer will be marked as brainliest. 15 points question.​

Answer 1

Answer:

1. - 125

2. a=7

3. a=12

Step-by-step explanation:

Pls refer to the attachment given below

Answer 2

Step-by-step explanation:

$a) \: x = - 4 \\ = 2 {( - 4)}^{3} + {( - 4)}^{2} + 5( - 4) + 7 \\ = 2( - 64) + 16 + ( - 20) + 7 \\ = - 128 + 16 - 20 + 7 \\ = - 125$

$b) \: p(x) = {x}^{2} + ax + 12 \\ when \: it \: is \: divided \\ \: by \: its \: factor(x + 3), \\ remainder = p( - 3) = 0 \\ { (- 3)}^{2} + a( - 3) + 12 = 0 \\ 9 + a( - 3) + 12 = 0 \\ a( - 3) + 21 = 0 \\ a+18 = 0 \\ a = -18$

sorry i don't know the 3rd question

hope it helps you