SOLUTION: 0.3(2r-3)=0.2r+0.9

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Question 619685: 0.3(2r-3)=0.2r+0.9
Answer by math-vortex(648) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, there--
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Solve for r.
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0.3%282r-3%29=0.2r%2B0.9
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First, distribute 0.3 across the parentheses.
0.6r-0.9=0.2r%2B0.9
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Now we will rewrite this equation as a series of equivalent equations until we have isolated the variable r.
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Combine like terms. Let's combine the variables on the left side of the equation. Subtract 0.2r from both sides.
0.6r-0.2r-0.9=0.2r-0.2r%2B0.9
0.4r-0.9=0.9
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Combine the constant terms on the right side of the equation. Add 0.9 to both sides of the equation.
0.4r-0.9%2B0.9=0.9%2B0.9
0.4r=1.8
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We want to know the value of 1r so we divide both sides of the equation by the coefficient of r; that is 0.4.
%280.4r%29%2F0.4=1.8%2F0.4%0D%0A%7B%7B%7Br=4.5
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We can check our work by substituting 4.5 for r in the original equation.
0.3%282r-3%29=0.2r%2B0.9
0.3%282%284.5-3%29%29=0.2%284.5%29%2B0.9
0.3%289-3%29=0.9%2B0.9
0.3%286%29=1.8
1.8=1.8
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This result shows that r=1.8 is the solution.
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Hope this helps. Feel free to email if you have questions about this solution,
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Ms.Figgy
math.in.the.vortex@gmail.com