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March 28, 2015

March 28, 2015

Posted by **manda** on Tuesday, April 10, 2007 at 10:24pm.

25+25+100+n=250

since x is in the first quadrant, then x+180º is in the third quadrant, and cos(x+180) = =cos x

You should recognize the 3,4,5 right-angled triangle and cosx = 3/5

so cos(x+180)=-3/5

3x+y=90+2x+y=90

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