EXAMPLE 9a. The sum of two numbers is 8. If one number is 3, find the other number.b. The...

EXAMPLE 9

a. The sum of two numbers is 8. If one number is 3, find the other number.

b. The sum of two numbers is 8. If one number is x, write an expression representing the other number.

c. An 8-foot board is cut into two pieces. If one piece is x feet, express the length of the other piece in terms of x.

Solution

a. If the sum of two numbers is 8 and one number is 3, we find the other number by subtracting 3 from 8. The other number is 8 − 3 or 5.

b. If the sum of two numbers is 8 and one number is x, we find the other number by subtracting x from 8. The other number is represented by 8 − x.

c. If an 8-foot board is cut into two pieces and one piece is x feet, we find the other length by subtracting x from 8. The other piece is (8 − x) feet.

Two numbers have a sum of 20. If one number is p, express the other number in terms of p.