Respuesta :

we have

[tex]42=d^2-22[/tex]

solve for d

[tex]\begin{gathered} d^2=42+22 \\ d^2=64 \\ \text{square root both sides} \\ d=\pm\sqrt[]{64} \\ d=\pm8 \end{gathered}[/tex]

therefore

d=+8 and d=-8