Express the polynomial as a product of linear factors. 3x^3+12x^2+3x-18

f(x) =  3(x + 2)(x - 1)(x + 3)

Step-by-step explanation:

A logical first step would be to factor 3 out of all four terms:

f(x) = 3x^3+12x^2+3x-18 = 3(x^3 + 4x^2 + x - 6)

Roots of this x^3 + 4x^2 + x - 6 could be factors of 6:  {±1, ±2, ±3, ±6}.

I would use synthetic division here to determine which, if any, of these possibilities are actually roots of x^3 + 4x^2 + x - 6.  Let's try x = 1 and see whether the remainder of this synth. div. is 0, which would indicate that 1 is indeed a root of x^3 + 4x^2 + x - 6:

1    /    1    4    1    -6

                1    5    6

          1     5    6    0

Yes, 1 is a root of x^3 + 4x^2 + x - 6, and so (x - 1) is a factor of x^3 + 4x^2 + x - 6.

Look at the coefficients of the quotient, which are   1, 5 and 6.

This represents the quadratic 1x² + 5x + 6, whose factors are (x + 2) and

(x + 3).

Thus, the given polynomial in factored form is:

f(x) = 3x^3+12x^2+3x-18 = 3(x + 2)(x - 1)(x + 3)

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240