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2 votes
Their sum is −7 and their difference is 14 what are my numbers

2 Answers

6 votes

Answer:

3.5,-10.5

Explanation:

User Arend
by
6.0k points
2 votes

Answer:

Answer: 3 1/2 and -10 1/2 are the two numbers.

Explanation:

Let x and y be the two unknown numbers.

x+y=-7 [Given]

x-y=14 [Given]

x-y=14 [Given]

x=y+14 [Add y to both sides]

x+y=-7 [Given]

(y+14)+y=-7 [Subtitution]

2y+14=-7 [Combine like terms]

2y=-21 [Subtract 14 from both sides]

y=-21/2 [Divide both sides by 2]

y=-10 1/2 [Division]

x-y=14 [Given]

x=y+14 [Add y to both sides]

x=-10 1/2 + 14 [Substitution]

x= 3 1/2 [Addition]

Check:

x+y=-7 [Given]

3 1/2 + -10 1/2?=-7 [Substition]

-7=-7 [Addition]

QED

x-y=14 [Given]

3 1/2 - -10 1/2?=14 [Substitution]

3 1/2 + 10 1/2?=14 [Change the sign of the subtrahend and add]

14=14 [Addition]

QED

Answer: 3 1/2 and -10 1/2 are the two numbers.

User Julio
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