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HELP HELP ME ASAP!!!

At LEAST ONE value of x MUST be 7 (x = 7 or x = ?)

My teacher said that a, b, and c ALL have to be greater than 0 and b has to be greater than 1

At LEAST ONE extraneous solution

HELP HELP ME ASAP!!! At LEAST ONE value of x MUST be 7 (x = 7 or x = ?) My teacher-example-1
User Sergey Belash
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1 Answer

18 votes
18 votes

Part a

Let
a=2. Then, we have that


7+2=√(7b+c)\\\\81=7b+c

We can let
b=11 and
c=4, meaning the equation is
x+2=√(11x+4).

Part b


x+2=√(11x+4)\\\\x^2 +4x+4=11x+4\\\\x^2 -7x=0\\\\x(x-7)=0\\ \\ x=0, 7

Substituting both of these values into the equation, we see they are both solutions.

Part c


x+10=√(10x+219)

User BondAddict
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