Question

A triangle has vertices on a coordinate grid at L(9,7), M (9, -8), and N(1,7). What is the length, in units, of LM?

Answer 1

Let:

`\begin{gathered} L=(x1,y1)=(9,7) \\ M=\mleft(x2,y2\mright)=\mleft(9,-8\mright) \end{gathered}`

Using the distance formula:

`\begin{gathered} d=\sqrt[]{(x2-x1)^2+(y2-y1)^2} \\ d=\sqrt[]{(-8-7)^2+(9-9)^2} \\ d=\sqrt[]{(15)^2+(0)^2} \\ d=\sqrt[]{225} \\ d=15 \end{gathered}`