Finding Two Numbers

Find two numbers with a sum of -66 and a difference of -116.

x = one number
y = other number

x + y = -66  {sum is -66}
x - y = -116  {difference is -116}
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2x = -182  {added the two equations together}
x = -91  {divided both sides by 2}

x + y = -66  {top equation}
-91 + y = -66  {substituted -91, in for x, into top equation}
y = 25  {added 91 to both sides}

Two numbers are -91 and 25

*To check*
-91 + 25 = -66  {sum is -66}
-91 - 25 = -116  {difference is -116}

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