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4 votes
Solve equations with variables on each side
3w+6=4w
a+18=7a
8c=5c+21

User Jhm
by
4.5k points

1 Answer

3 votes

Answer:

a) w=6

b) a=3

c) c=7

Explanation:


3w+6=4w


\mathrm{Subtract\:}6\mathrm{\:from\:both\:sides}


3w+6-6=4w-6


\mathrm{Simplify}


3w=4w-6


\mathrm{Subtract\:}4w\mathrm{\:from\:both\:sides}


3w-4w=4w-6-4w


\mathrm{Simplify}


-w=-6


\mathrm{Divide\:both\:sides\:by\:}-1


(-w)/(-1)=(-6)/(-1)


w=6

___________________________________________


a+18=7a


\mathrm{Subtract\:}18\mathrm{\:from\:both\:sides}


a+18-18=7a-18


\mathrm{Simplify}


a=7a-18


\mathrm{Subtract\:}7a\mathrm{\:from\:both\:sides}


a-7a=7a-18-7a


\mathrm{Simplify}


-6a=-18


\mathrm{Divide\:both\:sides\:by\:}-6


(-6a)/(-6)=(-18)/(-6)


a=3

User Pavel Kataykin
by
4.7k points