Question

Don't know how to do this

Answer 1

`\bf c^2=a^2+b^2\qquad \begin{cases} c=x\\ a=2√(2)\\ b=√(13) \end{cases}\implies x^2=(2√(2))^2+(√(13))^2 \\ \quad \\\\ x^2=2^2√(2^2)+√(13^2)\impliedby \textit{with the exponent distributed} \\\\ x^2=4\cdot 2+13\implies x^2=8+13\implies x^2=21 \\\\ √(x^2)=√(21)\impliedby \textit{now, we took }√(\qquad )\textit{ to both sides} \\\\ x=\pm √(21)`