13. 4x + y + 6 7
3x + 3y + 22-17
-x-y+z=-9

Two customers went to a post office. first customer paid $12 for 14 and 5 envelopes the second paid 24.80 for 10 postcards and 15 envelopes. what is cost of each envelope?

The roots of the function f(x) = x2 – 2x – 3 are shown. what is the missing number?

Aflagpole broke in a storm. 77 7 meters are still sticking straight out of the ground, where it snapped, but the remaining piece has hinged over and touches the ground at a point 2424 24 meters away horizontally