Question

The sun of two numbers is $189 and the difference is 15. What are the two numbers?

Answer 1

102 and 87

Explanation:

Let the two numbers be x and y.

x+y = 189

x-y =15

Add the two equations together.

x+y = 189

x-y =15

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2x =204

2x/2 = 204/2

x = 102

Now we can find y.

x+y = 189

102+y =189

y = 189-102

y =87