Why is the sum of a rational number and its opposite always equal to 0

What is the domain of C (X) = 0.07X + 5?

Simplify - 2/5 + 4/3 =

write an equation of a line in the slope intercept form when the slope is - 3/4 and the y intercept is 5

I forgot how to do this. - 2 (21+2y/5) + y=-8 Find y.

Four times the sum of a number and - 3 is 7 more than quadruple the number. Write and solve the equation to find the number.

A bag of marbles contains 4 green marbles, 3 blue marbles, 2 red marbles, and 5 yellow marbles. How many possible outcomes are there when choosing a marble from the bag

Last month, Korey's Comics had a gross profit of $2,385 with a monthly revenue of $3,465. Korey expects similar sales this month, but he would like to build up his in-store browsing selection, and purchases an additional assortment of comic books

There was a plate of cookies on the table. Amanda was hungry because she hadn't had breakfast, so she ate half the cookies. Then Beth came along and noticed the cookies. She thought they looked good, so she ate a third of what was left on the plate.

If sales tax is 5%, what is the sales tax on an item costing $65?

You pick a card at random. 2 3 4 5 What is P (5) ? 1% 25% 41% 11%