Inverse Operations with Exponent and Sum

Question

Struggling with this inverse operations formula (that I can't seem to remember since leaving college). Solve for $X$.

$$X^{\frac 12} + X = 5$$

Answer 1

we have $$\sqrt{x}=5-x$$ after squaring we obtain $$x=25-10x+x^2$$ solve this equation and check the Solutions

Answer 2

$$\sqrt{x}+x=5 \iff \sqrt{x}=5-x \iff x=25-10x+x^2 \iff x^2-11x+25=0$$

as long as $x\geqslant 0$.

Now use the quadratic formula to get an explicit formula for $x$.