[tex]\begin{gathered} \text{ }\sqrt[]{42}\text{ + }\sqrt[]{63} \\ =\sqrt[]{42}\text{ = 6.4807} \\ \sqrt[]{63}=7.9373 \\ \sqrt[]{42}\text{ + }\sqrt[]{63}\text{ = 6.4807 + }7.9373 \\ =14.4180 \\ To\text{ 1 decimal place, we have 14.4} \\ \text{ The answer is 14.4} \end{gathered}[/tex]