Question 74034
{{{a(a-3)-2a(a-4)=-(a^2-4a)+6}}}
{{{a^2-3a-2a^2+8a=-a^2-4a+6}}}Distribute the a and the 2a to their respective terms
{{{a^2+a^2-3a-4a-2a^2+8a-6=0}}}Get all terms to one side
{{{2a^2-2a^2-7a+8a-6=0}}}
{{{0a^2+a-6=0}}}Add and subtract like terms
{{{a=6}}}Add 6 to both sides
So a is 6.
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Check:
{{{a(a-3)-2a(a-4)=-(a^2-4a)+6}}}
{{{6(6-3)-2(6)(6-4)=-(6^2-4(6))+6}}}Plug in a=6
{{{6(3)-12(2)=-(36-24)+6}}}
{{{18-24=-12+6}}}
{{{-6=-6}}}Works