Simplify the expression by combining like terms.
2x + 4y + 6 + 2y - 5 + 3x 

1mile equals approximately 1.6 kilometers. which best approximates the number of miles in 6 kilometers?

Adj has a total of 1075 dance and rock songs on her system. the dance selection is 4 times the size of the rock selection. write a system of equations to represent the situation.

The volume of gas a balloon can hold varies directly as the cube of its radius. imagine a balloon with a radius of 3 inches can hold 81 cubic inches of gas. how many cubic inches of gas must be released to reduce the radius down to 2 inches?