Simplify the expression 20(x+y)−19(y+x) for all values of x and y.
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Solution
Simplifying, we see that 20(x+y)−19(y+x)=20x+20y−19y−19x=x+y for all values of x and y.
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