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Four Unknowns, Three Equations

Pro Problems > Math > Algebra > Equations > Systems of Equations > Word Problems > Many Variables
 

Four Unknowns, Three Equations

Find the sum of x, y, z, and w if

3x + y = 170
y + 3z = 50
z + x - 2w = 30 

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Problem by Mr. Twitchell

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