SOLUTION: 7c(8c+7)=3c-15

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Question 114044:
7c(8c+7)=3c-15
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
7C(8C+7)=3C-15
56C^2+49C-3C+15=0
56C^2-46C+15=0
USING THE QUADRATIC EQUATION:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ WE GET:
C=(46+-SQRT[-46^2-4*56*15])/2*56
C=(46+-SQRT[2116-3360])/112
C=(46+-SQRT-1244)/112
C=(46+-35.37i)/112
C=46/112+35.37i/112
C=.41+.3158i ANSWER.
C=46/112-35.37i/112
C=.41-.3158i ANSWER.