Dominic pays 7% interest on his $16,000 college loan and 12% interest on his $15,000 car loan. What average interest rate does he pay on the total $31,000 he owes? (Round your answer to the nearest tenth of a percent.)​

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.

4y - 6 + y^2 - 9 = y^2 + 4y - 15

y^2 term

terms

- terms

total of 3 terms when simplified

step-by-step explanation: