4x = 100 divide both sides by 4
x = 25 → c.
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5x = 25 divide both sides by 5
x = 5 → c.
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3x + 5 = 17 subtract 5 from both sides
3x = 12 divide both sides by 3
x = 4 → a.
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3x + 14 = 11 subtract 14 from both sides
3x = -3 divide both sides by 3
x = -1 → b.
