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Question
Verify by substitution that the root of 3x − 5 = 7 is x = 4.
Solution
3x - 5 = 7
Substituting x = 4 in the given equation:
L . H . S .
3 × 4 - 5
or, 12 - 5 = 7 = R. H. S.
L. H. S. = R. H. S.
Hence, x = 4 is the root of the given equation.
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