SOLUTION: If A B=10, B C=12 and A C=15 .what is the value of A ?

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Question 914529: If A B=10, B C=12 and A C=15 .what is the value of A ?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Re TY '+' didn't come thru :), Principle the same...
A+B = 10 0r A = 10-B
B+C = 12 0r C = 12-B
A+C = 15
(10-B) + (12-B) = 15
22-2B = 15
7 = 2B, B = 3.5 , A = 6.5 10-3.5, C = 8.5 12-3.5
.............
AB = 10 0r A = 10/B
BC = 12 0r C = 12/B
AC = 15
%2810%2FB%29%2812%2FB%29 = 15
%2810%2A12%2F15%29 = B^2
B^2 = 8
B = ± sqrt%288%29 = ± sqrt%284%2A2%29
B = ± 2√2
A = 10/B = ± 10%2F%282sqrt%282%29%29 = ±5sqrt%282%29%2F2