What does x represent?

15x-12y=13

30x+9y=4

What happens to the value of the expression b-1 as b increases

There is a fraction that is equivalent to 9/10. The sum of its numerator and denominator is 57. What is the fraction?

a movie complex is showing the same movie in three theaters. In theater A, 112 of the 160 seats are filled. In theater B, 84 seats are filled and 56 seats are empty. In theater C, 63 of the 180 seats are empty.

The nile river, the longest river in the world, is 66.7x100 kilometers long. What is the nile's length?

Heather bought enough shells to make x necklaces. Each necklaces holds 16 shells. Heather has made 10 necklaces. Is 16x + 10 a reasonable way to represent the number of shells that Heather has left to make necklaces with? Explain your answer.

On Saturday Elena biked 10 miles. On Sunday she biked 50% of that distance. How far did she travel on Sunday?

Coffee costs $12 per case, and tea costs $8 per case. If an order comes in for a total of 250 cases for $2,600, what was the specific number of cases of tea? (Hint: Let C = cases of coffee.)

Factor completely 4x^2-32 4 (x+4) (x-4) 4 (x+4) (x-8) 4 (x^2-8) Prime

Each student in a class plays one of three sports soccer, volleyball or basketball. 1/4 of them play soccer. 3/5 of them play volleyball. How many of them play basketball?

What is the answer to the problem: 45.8 m x 0.385 m x 5.81 m? a. 102.448m^3 b. 102.45 m^3 c. 102.4 m^3 d. 102 m^3