Question

The sum of two rational numbers of 63, and their difference is 12? What are the numbers?

Answer 1

The two numbers are 37.5 and 25.5

Explanation:

Comment

Let the two numbers be x and y

Equations

x + y = 63

x - y = 12

Solution

Add the two equations. The ys cancel out.

2x = 75 Divide by 2

2x/2 = 75/3 Do the division

x = 37.5

Now use one of the given equations to solve for y

x + y = 63

x = 37.5

37.5 + y = 63 Subtract 37.5 from both sides

37.5-37.5+y= 63 - 37.5 Collect the like terms on both sides

y = 25.5

Check

x - y =? 12

37.5-25.5 =? 12

12 = 12