Respuesta :

Answer:

a = -3

Step-by-step explanation:

f(x) = 5x³+4x²+3x-4a

f(-1) = 8

therefore , x = -1

substituting x = -1 in 5x³ + 4x² +3x-4a

5(-1)³ + 4(-1)² + 3(-1) - 4a. = 8

-5 + 4 -3 - 4a = 8

-8 + 4 -4a = 8

-4 - 4a = 8

shifting -4 from LHS to RHS

-4a = 8+4

-4a = 12

[tex] - a = \frac{12}{4} [/tex]

therefore

-a = 3

a = -3

ANS = the value of a = -3

if you r having any queries please comment down and make it brainlist answer if you liked it and hit a like too!!!!!!

RELAXING NOICE
Relax