Q1 of 105 Page 280

Find the errors and correct the following mathematical sentences

Substitute x = – 3 in


(c) x2 + 5x = (–3)2 + 5 (–3) + 6 = – 9 – 15 = –24

If LHS is


x2 + 5x


Then RHS would be


⇒ x2 + 5x


Putting x = (-3)


= (–3)2 + 5 (–3)


= 9 + (-15)


= -6


The error is ( + 9) instead of (-9) and end results to (-6) instead of (-24)


Hence putting x = (-3) in x2 + 5x results to (-6)


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