Show how to add 2 + 1/2 + 4/5 ​

Aswimming pool had 2.5 million liters of water in it. some water evaporated, and then the pool only had 22 million liters of water in it. what percent of the water evaporated?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

Write the point-slope form of the line passing through (2, -12) and parallel to y=3x.