Simplify (6x^2-8x+9)+(4x^3-6x-+2x^2-7)

Which equation can be used to solve for the unknown number? seven less than a number is thirteen. n-7=13 7-n=13 n+7=13 n+13=7

Solve the equation for x.3(6x - 1) = 12 i've tried doing the math and i can't find out what i'm doing wrong

Out of 50 students surveyed, 16 have a dog. based on these results, predict how many of the 280 students in the school have a dog.