2023 · Q11
How many real roots does the equation √(x + 9) = x − 3 have?
Elementary MathematicsAlgebra
- AOnly one
- BOnly two
- COnly three
- DNone
Explanation
Need x>=-9 and x-3>=0, so x>=3. Squaring: x+9=x^2-6x+9, i.e. x(x-7)=0. x=0 is extraneous; x=7 satisfies 4=4. Exactly one real root. Option (a).