Question 398730
Find the measure of each angle A=(x+10), b=(x-10), c=(3x-50)
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Equation:
x+10 + x-10 + 3x-50 = 180
5x-50 = 180
5x = 230
x = 46
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A = x+10 = 56 degrees
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B = x-10 = 36 degrees
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C = 3x-50 = 3*46-50 = 138-50 = 88 degrees
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and 
RI invested some money at 9% and $100 less than at 7%. Her total annual interest was $81. How much did she invest at each rate?
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Interest Equation:
0.09x + 0.07(x-100) = 81
Multiply thru by 100 to get:
9x + 7x-700 = 8100
16x = 8800
x = $550 (amt. invested at 9%)
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x-100 = $450 (amt. invested at 7%)
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Cheers,
Stan H.
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