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Solve the radical equation. Check for extraneous solutions. Circle the solution to the equation.

√(2x+3) = x

1 Answer

5 votes

Answer:

The solution to the equation is x=3.

Explanation:

Write the equation:

√(2x+3)=x

Square both sides to get rid of the radical sign:

(√(2x+3))^2=(x)^2

2x+3=x^2

Subtract 2x from both sides:

2x-2x+3=x^2-2x

3=x^2-2x

Subtract 3 from both sides:

3-3=x^2-2x-3

0=x^2-2x+3

x^2-2x-3=0

Solve using the Quadratic Formula:

x=(-b±√(b^2-4ac))/2a

Plug values in for a, b, and c: (a=1, b=-2, c=-3)

x=(-(-2)±√((-2)^2-4×1(-3) ))/(2×1)

Solve:

x=(2±√(4-4(-3) ))/(2×1)

x=(2±√16)/(2×1)

x=(2±4)/(2×1)

x=(2±4)/2

x=(2+4)/2

x=6/2

x=3

x=(2-4)/2

x=-2/2

x=-1

So, the POSSIBLE solutions are x=3 and x=-1. Now, find the real solution, or value, of x.

Plug 3 back into the equation as x:

√(2x+3)=x

√(2(3)+3)=3

√(6+3)=3

√9=3

3=3 ✔

Plug –1 back into the equation as x:

√(2x+3)=x

√(2(-1)+3)=-1

√(-2+3)=-1

√1=-1

1≠-1 ❌

So, the REAL solution to √(2x+3)=x is x = 3.

Hope that helps! Have an amazing rest of your day! :)

User Grahame A
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