# Algebra

posted by
**Maddy**
.

please help me with this question and check my answers.

Solve the problem.

A rectangle with width 2x + 5 inches has an area of 2x4 + 9x3 - 12x2 - 79x - 60 square inches. Write a polynomial that represents its length. ( I don't know how to solve this problem)

Use synthetic division and the Remainder Theorem to find the indicated function value.

f(x) = x^4 + 4x^3 + 8x^2 - 5x + 3; f(-2)

I GOT 29

f(x) = 4x^3 - 3x^2 - 3x + 20; f(-2)

i got -18

f(x) = 6x^4 + 9x^3 + 5x^2 - 6x + 24; f(-3)

i got 330

Use synthetic division to divide f(x) = x^3 + 7x^2 - 6x - 72 by x + 4. Use the result to find all zeros of f.

-i got {-4,-6,3}

Use synthetic division to show that the number given to the right of the equation is a solution of the equation, then solve the polynomial equation.

x^3 + 5x^2 + 2x - 8 = 0; -2

i got {1,-4,-2}