Question 224708
{{{-2x+5+4x=21}}}


Step 1.  Combine like terms (in this case x-terms)


{{{(-2+4)x=5=21}}}


{{{2x+5=21}}}


Step 2.  Subtract 5 from both sides of the equation


{{{2x+5-5=21-5}}}


{{{2x=16}}}


Step 3.  Divide 2 to both sides of the equation


{{{2x/2=16/2}}}


{{{x=8}}}


Step 4.  ANSWER:  Solution is {{{x=8}}}


I hope the above steps were helpful.


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Good luck in your studies!


Respectfully,
Dr J