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Completion requirements
Solve the following radical equations. Verify your solutions.
- \(\sqrt {y - 1} = 7\)
\(\begin{align}
y - 1 &\ge 0 \\
y &\ge 1, y \in \rm R \\
\end{align}\)
\(\begin{align}
\sqrt {y - 1} &= 7 \\
\left( {\sqrt {y - 1} } \right)^2 &= 7^2 \\
y - 1 &= 49 \\
y &= 50 \\
\end{align}\)
Verify:
Left Side
Right Side
\(\begin{array}{r}
\sqrt {y - 1} \\
\sqrt {50 - 1} \\
\sqrt {49} \\
7 \\
\end{array}\)
\(7\) LS = RS - \(\sqrt[5]{{4x}} = 2\)Because the index is \(5\) (odd), there are no restrictions on the variable, \(x \in \rm R\).
\(\begin{align}
\sqrt[5]{{4x}} &= 2 \\
\left( {\sqrt[5]{{4x}}} \right)^5 &= 2^5 \\
4x &= 32 \\
x &= 8 \\
\end{align}\)
Verify:
Left Side
Right Side
\(\begin{array}{r}
\sqrt[5]{{4x}} \\
\sqrt[5]{{4\left( 8 \right)}} \\
\sqrt[5]{{32}} \\
2 \\
\end{array}\)
\(2\) LS = RS\(\hspace{30pt}\)