Question

30-×20, ×+1=40, y-8=7.

Answer 1

30 - X = 20
X =30 - 20
X =10
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30 - 10 = 20
20 = 20

X + 1 = 40
X =40 - 1
X = 39
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39 + 1 = 40
40 = 40

Y - 8 = 7
Y = 8 + 7
Y = 15
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15 - 8 = 7
7 = 7