Find 2 numbers such that the difference between them is 20 and their sum is -4.

Is there a systematic way or method to solve this besides just guessing integers?

(p.s. No algebra allowed, this is a pre-algebra questions)

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- Oct 27th 2010, 02:30 AMKickFind two numbers where difference is 20 & the sum is -4
Find 2 numbers such that the difference between them is 20 and their sum is -4.

Is there a systematic way or method to solve this besides just guessing integers?

(p.s. No algebra allowed, this is a pre-algebra questions) - Oct 27th 2010, 03:25 AMAckbeet
The only systematic way to solve this that I know of is to use linear algebra:

x - y = 20

x + y = -4.

Turn the crank. - Oct 27th 2010, 03:35 AMRHandford
Hi

A clue, one of the numbers you want is 8, can you work out the other number? - Oct 27th 2010, 05:26 AMHallsofIvy
Divide the difference equally between the two numbers.

Half of 20 is 10, half of -4 is -2. Add and subtract -2 to and from 10.

Think about what the signs should be.

(As Ackbeet implies "systematic" pretty much**means**algebra!) - Oct 27th 2010, 10:33 AMwonderboy1953