SOLUTION: I need help solving the proportion X/X^2+4=7/5x. please and thank you

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Question 140741This question is from textbook
: I need help solving the proportion X/X^2+4=7/5x. please and thank you This question is from textbook

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
YOU SHOULD USE ( ) IN THESE TYPE OF EQUATIONS BECAUSE THERE ARE MULTIPLE WAYS OF INTERPRETING THEM AS YOU CAN SEE BELOW.
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X/X^2+4=7/5x.
IF THIS EQUATION IS:
X/(X^2+4)=(7/5X) THEN:
7(X^2+4)=5X^2
7X^2+28-5X^2=0
2X^2=28
X^2=28/2
X62=14
X=SQRT14
X=3.74 ANSWER.
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IF THIS EQUATION IS
(X/X^2)+4=7X/5 THEN:
(1/X)+4=7X/5
(1+4X)/X=7X/5
X*7X=5(1+4X)
7X^2=5+20X
7X^2-20X-5=0
USING THE QUADRATIC EQUATIONx+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+WE GET:
X=3.09 & X=-.231
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IF THE EQUATUON IS:
X/(X^2+4)=7X/5 THEN:
7X(X^2+4)=5X
7X^3+28X-5X=0
7X^3+23X=0
X(7X+23)=0
X=0 ANSWER.
7X+23=0
7X=-23
X=-23/7 ANSWER.