Question 54027
1) This can be simplified by multiplying everything by 10 to eliminate the decimals.
{{{2.1x+45.2=3.2-8.4x}}}
{{{10(2.1x)+10(45.2)=10(3.2)+10(-8.4x)}}}
{{{21x+452=32-84x}}}
{{{84x+21x+452=32-84x+84x}}}
{{{105x+452=32}}}
{{{105x+452-452=32-452}}}
{{{105x=-420}}}
{{{105x/105=-420/105}}}
{{{cross(105)x/cross(105)=-4}}}
{{{highlight(x=-4)}}}
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2) This can be simplified by multiplying everything by the LCD, 3.
{{{(1/3)(2x-1)=7}}}
{{{3(1/3)(2x-1)=3(7)}}}
{{{(cross(3)/cross(3))(2x-1)=21}}}
{{{2x-1=21}}}
{{{2x-1+1=21+1}}}
{{{2x=22}}}
{{{cross(2)x/cross(2)=22/2}}}
{{{highlight(x=11)}}}
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3) This can be simplified by multiplying both sides of = sign by LCD,30.
{{{(1/6)((3/4)x-2)=-1/5}}}
{{{30(1/6)((3/4)x-2)=30(-1/5)}}}
{{{(30/6)((3/4)x-2)=-30/5}}}
{{{5((3/4)x-2)=-6}}}
{{{(15/4)x-10=-6}}}
{{{(15/4)x-10+10=-6+10}}}
{{{(15/4)x=4}}}
{{{(cross(4)*15/cross(4))x=4*4}}}
{{{15x=16}}}
{{{cross(15)x/cross(15)=16/15}}}
{{{highlight(x=16/15)}}}
Don't let fractions and decimals unnerve you. Annihalate them before you get started!
Happy Calculating!!!