Respuesta :
Answer: The correct option is C.
Explanation:
The given expression is,
[tex]\sqrt{b+20}- \sqrt{b}=5[/tex]
We have to choose the correct process to solve this equation.
Add a radical term [tex]\sqrt{b}[/tex] both sides.
[tex]\sqrt{b+20}=5+\sqrt{b}[/tex]
Now square both sides.
[tex](\sqrt{b+20})^2=(5+\sqrt{b})^2[/tex]
[tex]b+20=25+b+10\sqrt{b}[/tex]
[tex]b-20-25-b=10\sqrt{b}[/tex]
[tex]-5=10\sqrt{b}[/tex]
[tex]\sqrt{b} =\frac{-1}{2}[/tex]
Square both sides.
[tex]b=\frac{1}{4}[/tex]
The process is Add a radical term to both sides and square both sides twice.
Therefore, C is the correct option.