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**Mr Rayon** *The remainder when x^3 + ax^2 + bx + 1 is divided by (x - 5) is -14. When the cubic polynomial is divided by (x + 1), the remainder is -2. Find a and b.*

To solve a and b, I did the following:

P(5) = 5^3 + a(5)^2 + b(5) + 1

= 125 + 25a + 5b + 1

= 25a + 5b + 126

25a + 5b + 126 = -14

P(-1) = (-1)^3 + a(-1)^2 + b(-1) + 1

= -1 + a - b + 1

= a - b

a - b = -2

Using the method of elimination:

25a + 5b = -140

25a - 25b = -50

30b = -190 Mr F says: -140 - (-50) = -90. So you should have 30b = -90.

b= -19/3

Substituting the value of b into: a - b = -2

a - (-19/3) = -2

a + 19/3 = -2

a = -25/3

But the answers are supposed to be:

a = -5, b= -3

*What did I do wrong? Please show me complete working out. All help will be appreciated.*