Use addition or substitution to solve this problem.
To paint his house, Samuel bought 2 cans of paint and one roller for $30. When friends came over to help, he went back to the store and bought three more cans of paint and two more rollers for $50. How much did he pay for a can of paint?

Question

anonymous · Answer

use p to represent paint cans and r to represent rollers.

anonymous · Answer

2p + r = $30
p + 2r = $50

anonymous · Answer

the second equation should be 3p + 2r = $50. sorry!

anonymous · Answer

do you understand what i did?