Question 229434
Given {{{10(x+3)=4x+6}}}


prove x=-4


Step 1.  Multiply out the left side of the equation to get rid of the parenthesis.


{{{10x-30=4x+6}}}


Step 2.  Subtract 30 from both sides of the equation 


{{{10x+cross(30)-cross(30)=4x+6-30}}}


{{{10x=4x-24}}}


Step 3.  Subtract 4x from both sides of the equation


{{{10x-4x=cross(4x)-24-cross(4x)}}}


{{{6x=-24}}}


Step 4.  Divide 6 from both sides of the equation


{{{cross(6)x/cross(6)=-24/6}}}


{{{x=-4}}}


Step 5. Check {{{x=-4}}} as a solution by substituting into original equation {{{10(x+3)=4x+6}}}


{{{10(-4+3)=4*(-4)+6}}}


{{{-10=-10}}} which is a true statement.


Step 6.  ANSWER:  The solution is {{{x=-4}}}.  Steps 1-5 shows the proof.


I hope the above steps were helpful.


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Respectfully,
Dr J

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