Questions: Solve the radical equation. Check all proposed solutions.
√x + 8 = x + 2
Transcript text: Solve the radical equation. Check all proposed solutions.
\[
\sqrt{x}+8=x+2
\]
Solution
Solution Steps
Step 1: Isolate the Radical
Start with the original equation:
\[
\sqrt{x} + 8 = x + 2
\]
Isolate the radical by moving all other terms to the right side:
\[
\sqrt{x} = x + 2 - 8
\]
This simplifies to:
\[
\sqrt{x} = x - 6
\]
Step 2: Square Both Sides
Square both sides to eliminate the radical:
\[
(\sqrt{x})^2 = (x - 6)^2
\]
This results in:
\[
x = x^2 - 12x + 36
\]
Step 3: Rearrange to Form a Quadratic Equation
Rearrange the equation to set it to zero:
\[
0 = x^2 - 12x + 36 - x
\]
This simplifies to:
\[
0 = x^2 - 13x + 36
\]
Step 4: Solve the Quadratic Equation
Factor the quadratic equation:
\[
0 = (x - 9)(x - 4)
\]
Setting each factor to zero gives the potential solutions:
\[
x - 9 = 0 \quad \Rightarrow \quad x = 9
\]
\[
x - 4 = 0 \quad \Rightarrow \quad x = 4
\]
Step 5: Check Each Solution
Substitute \( x = 9 \) back into the original equation:
\[
\sqrt{9} + 8 = 9 + 2
\]
This simplifies to:
\[
3 + 8 = 11 \quad \Rightarrow \quad 11 = 11 \quad \text{(valid)}
\]
Now check \( x = 4 \):
\[
\sqrt{4} + 8 = 4 + 2
\]
This simplifies to:
\[
2 + 8 = 6 \quad \Rightarrow \quad 10 \neq 6 \quad \text{(not valid)}
\]