Question

if kx³+9x²+4x-10 is dividing by x+3 it leaves the remainder 5, find the value of k ​

Answer 1

• x + 3 = 0

=> x = - 3

» Put value of x in kx³ + 9x² + 4x - 10 = 5

=> k(-3)³ + 9(-3)² + 4(-3) - 10 = 5

=> - 27k + 81 - 12 - 10 = 5

=> - 27k + 59 = 5

=> - 27k = 5 - 59

=> - 27k = - 54

=> k = $\dfrac{54}{27}$

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$\textbf{k = 2}$

_____________ [ANSWER]

Answer 2

Answer:

kx^3+9x^3+4x-10=5

If x+3 is its factor, then x=-3

Putting the value of x in the equation

k(-3)^3+9(-3)^2+4(-3)-10=5

=> -27k+81-12-10=5

=> -27k +59=5

=> -27k =-54

=> k= 54/27

=> k= 2

Hence, the value of k is 2