Solve for x
x=7.5
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8+4.5+x=20
Add 4 and 4 to get 8.
12.5+x=20
Add 8 and 4.5 to get 12.5.
x=20-12.5
Subtract 12.5 from both sides.
x=7.5
Subtract 12.5 from 20 to get 7.5.
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Matrix
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Simultaneous equation
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Limits
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