Sam collects insects. However, he only

collects ants and beetles. One night while

collecting insects for his collection, Sam had

an unproductive hunt. The number of ants

plus twice the number of beetles was only

eight. The difference between the number of

ants and beetles was -4. How many ants and

how many beetles did he catch?

1 answer

a + 2b = 8
a - b = -4

Multiply the second equation by -1.

-a + b = 4

Add the two equations:

3b = 12

b = 4

Put 4 into one equation:

a + 2(4) = 8

a + 8 = 8

a = 0

He caught 0 ants and 4 beetles.