Solve the system by substitution.
-8x – 7y = -5
-x = y

Aregular hexagon has sides of 2 feet. what is the area of the hexagon? 12 ft2 12 ft2 24 ft2 6 ft2

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?

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?