To calculate the distance between 2 points we will use the following equation:
[tex]D=\sqrt[]{(x_2-x_1)^2-(y_2-y_1)^2}[/tex]For this exercise we have the following data:
[tex]\begin{gathered} D=18 \\ x_1=7 \\ x_2=-3 \\ y_1=y \\ y_2=8 \end{gathered}[/tex]We plug the values into the distance equation and solve for the unknown Y
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