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justin.lam06
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Word Problems Ch 10 Medium Qs, #8, answer on p. 193

by justin.lam06 Sun Nov 09, 2014 6:11 pm

In the solution, can you explain a bit more how you go from 2v-360 = 3c to 2(3c - 360) = 3c?
tommywallach
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Re: Word Problems Ch 10 Medium Qs, #8, answer on p. 193

by tommywallach Sun Nov 09, 2014 11:36 pm

Hey Justin,

They're combining their two equations at that step. In the previous equation (bottom of the last page), they said that v = 3c. So at this point, they're plugging in 3c for v.

Hope that helps!

-t
danc
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Re: Word Problems Ch 10 Medium Qs, #8, answer on p. 193

by danc Fri Nov 28, 2014 2:50 pm

There is a typo in that line that might be confusing. When they plug in 3C for V the "close parenthesis" is in the wrong place. It should read 2(3C)—360=3C. After that, everything follows normally and the answer is correct. But, with the parenthesis where they are in the book, 2(3C—360)=3C, you'd have to distribute the multiplication by 2 to the 360 as well leaving you with 6C—720=3C, which would yield the wrong answer.
tommywallach
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Re: Word Problems Ch 10 Medium Qs, #8, answer on p. 193

by tommywallach Fri Nov 28, 2014 8:17 pm

Hey Dan. We shall get that sorted!

-t