Solve this equation? I don't get it.

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2 Answers
Mar 11, 2018

See the steps below

Explanation:

We are trying to get what #m# equals, so we must isolate it

#m+200=204 rarr# Multiply each side by 4

#m=4 rarr# Subtract 200 from each side

#m=4# is your answer

Mar 11, 2018

#m = 4#

Explanation:

You are looking for values of #m# that satisfy the given equation.

The simple rule is, if you do something to one side of the equation, then you must do the same thing to the other side of the equation to maintain the equality.

I am trying to isolate #m# by itself on one side. To unpick the mess, I note that an expression in #m# (specifically, #m + 200#) is divided by #4#. If I multiply the left hand side by #4#, I can get rid of the #4# at the bottom of the fraction (where it is called the denominator). I have to do the same to both sides, so

#(m + 200)/4 = 51#

implies

#4 xx (m + 200)/4 = 4 xx 51#

which may be written

#4/4 xx (m + 200) = 4 xx 51#

and hence (because #4/4 = 1#)

#m + 200 = 204#

To unpick the presence of the 200 on the left hand side, I can subtract 200 from both sides

#m + 200 = 204#

implies

#m + 200 - 200 = 204 - 200#

and hence (because #200 - 200 = 0#)

#m = 204 - 200#

that is,

#m = 4#

(you might note the rule of moving the 200 from one side of the equation to the other and reversing its sign)