How do you solve and check your solutions to #1/2m=21#?

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Answer 1 · 2016-09-27T11:24:42

#m = 42#

Estimate the answer first..

"Half of something is 21"..... the whole something is 42

Do the maths..

#color(red)(2xx)1/2 m = color(red)(2xx)21" "larr xx 2# on both sides to cancel

#m = 42#

TO check: substitute 42 in the place of m.

#1/2 (42)#

=#21#

This is the same as the answer that was given, so we have the correct value for m.