Question

find the value of p if 2x^3 - 5x^2 + px - 7 = 10 , x = -1​

Answer 1

Answer:

p = 0

Explanation:

2x^3 - 5x^2 + px - 7 = 10

2(-1)^3 - 5(-1)^2 + p(-1) - 7 = 10

(-2)^3 - (-5)^2 + (-p) - 7 = 10

-8 + 25 + (-p) - 7 = 10

10 (-p) = 10

p = 0

Answer 2

Answer:

-24

Explanation:

$2 {x}^{3} - 5 {x}^{2} + px - 7 = 10$

but we have given,

x = -1

$2 \times { - 1}^{3} - 5 \times { - 1}^{2} + p \times ( - 1) - 7 = 10$

$2 \times - 1 - 5 \times 1 - p - 7 = 10$

$- 2 - 5 - p - 7 = 10$

$- 14 - p = 10$

$- p = 10 + 14$

$- p = 24$

$p = - 24$