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The difference of two numbers is seven and there’s some is 49 find the two numbers please hurry!!!

User Chris Maes
by
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1 Answer

3 votes

Answer: The two numbers are 28 and 21

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Step-by-step explanation:

Let x and y be the unknown numbers.

The two equations we're dealing with are


\begin{cases} x-y = 7\\ x+y = 49\\ \end{cases}

The first equation talks about the difference being 7, and the second equation says their sum is 49. It's implied that x > y.

Add the equations straight down.

  • The x terms add to 2x
  • The y terms add to 0y, and go away
  • The constants add to 7+49 = 56

We're left with 2x = 56 which solves to x = 28. Divide both sides by 2 to isolate x fully.

Then use this x value to find y. Pick on any equation with x and y in it.

Let's say we picked the first equation

x-y = 7

28-y = 7

-y = 7-28

-y = -21

y = 21

Or you could pick the second equation

x+y = 49

28+y = 49

y = 49-28

y = 21

Either way, we end up with the same y value.

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As a check:

x-y = 28-21 = 7

x+y = 28+21 = 49

The answers are confirmed.

User Anorov
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