Question by mebunches2001 (answered by Mr F)

Asked today 03:43 PM by mebunches2001 at his/her Visitor Messages:

My grangson came home with math that I cannot help him with. I have tried all I can and need help! There are four problem solving questions. Instructions - Read the clues. Write the number pairs. #1 The sum is 10. The difference is 0. Both numbers are equal. #2 The difference is 2. The sum is 8. The numbers are not equal. #3 The sum is 1 less than 10. The difference is 1. One number is greater than 4. #4 The sum is 7. The difference is 7. One number is greater than 6.
#1)
x + y = 10 .... (1)
x - y = 0 .... (2)

Solve equations (1) and (2) simultaneously by adding them together:

(1) + (2): 2x = 10 => x = 5.

Substitute x = 5 into equation into (1) and solve for y: 5 + y = 10 => y = 5.

#2)
x - y = 2 .... (1)
x + y = 8 .... (2)

Solve in a similar way to #1.

#3)
x + y = 10 - 1 => x + y = 9 .... (1)
x - y = 1 .... (2)

Solve in a similar way to #1.

#4)
x + y = 7 .... (1)
x - y = 7 .... (2)

Solve in a similar way to #1.