Solve for r.

4r-9s=K

Write y=-3x^2-18x-31 in vertex form

What is the greatest common factor of 28 and 11

Alonzo rented a truck for one day. There was a base fee of $15.99, and there was an additional charge of 89 cents for each mile driven. Alonzo had to pay $184.20 when he returned the truck. For how many miles did he drive the truck?

There are 80 students in a speech contest. Yesterday, 1/4 of them gave their speeches. Today, 3/5 of the remaining students gave their speeches. How many students still haven't given their speeches?

Seth is going to be a junior in high school, and the college he wants to go to costs $9,264 for tuition the first year. Seth's parents have a savings account that will cover 75% of his first year's tuition, and the rest Seth will need to pay for.

IThe first three terms of a sequence are given. Round to the nearest thousandth (if necessary). 72, 24, 8, ... Find the 8th term.

A cannery processed 735 pounds of strawberries in 3.5 hours. The cannery processed 2100 pounds in 10 hours. a. Write an equation using function notation to model the weight of strawberries s processed in t hours. b.

At Kent Middle School, there are 104 students in the band and 80 students in the choir. What percent of the number of students in the choir is the number of students in the band

Solve the problem. Sergio's internet provider charges its customers $7 per month plus 3¢ per minute of on-line usage. Sergio received a bill from the provider covering a period and was charged a total of $28.70.

Two lines, parallel to the bases of a trapezoid divide each leg into three congruent parts and divide the trapezoid into three parts as well. Find the area of the middle part if the top and bottom parts have area S1 and S3.