Question

1. The sum of two numbers is 20.5. Their
difference is 6.5. Find the two numbers.

Answer 1

The two numbers are 7 and 13.5

Explanation:

Let the two numbers be x and y

Make 3 equations (for system of equation and substitution method)

Equation 1. x - y = 6.5

Equation 2. x = 6.5 + y

Equation 3. x + y = 20.5

Use the value of x in equation 2 to substitute x in equation 3.

6.5 + y + y = 20.5

Combine like terms

6.5 + 2y = 20.5

- 6.5 on both sides

2y = 14

Divide both sides by 2 to isolate y

y = 7

Substitute y in equation 3 to find x

x + 7 = 20.5

x = 13.5

Hope this helps :)

Have a great day!

Answer 2

13.5 and 7

Explanation:

x + y = 20.5

× - y = 6.5

Hence,

x =20.5 - y

20.5 - 2y = 6.5

Hence,

2y = 14

and x = 20.5 - 20.5 - 7 = 13.5

Hope that helps :))