Question

the difference between 2 numbers, a and b is 21. the difference of 5 times a and 2 times b is 18. What are the values of a and b?

Answer 1

Explanation:

a-b=21

5a-2b=18

Using elimination, we have

5a-5b=105

5a-2b=18

So:

3b=-87 so b=-29

Substituting, a=-8

(a,b)=(-8,-29)