Question

(5x+28) (7x+4) find the value of x

Answer 1

Answer:

given p(x)= 5x^3-7x^2-ax-28

(x-4) is a factor of 5x^3-7x^2-ax-28

=>p(4)=0

=>5(4)^3-7(4)^2-4a-28=0

=>320-112-4a-28=0

=>-4a=-180

=>a=180/4

=>a=45

Step-by-step explanation:

x=a