Answer :

A triangle has vertices on a coordinate grid at D(-10, -1), E(-10,6), and F(2,6). What is the length, in units, of DE?​

we know that

The formula to calculate the distance between two points is equal to

[tex]d=\sqrt[]{(y2-y1)^2+(x2-x1)^2}[/tex]

we have

D(-10, -1), E(-10,6)

substitute the given values in the formula

[tex]\begin{gathered} d=\sqrt[]{(6+1)^2+(-10+10)^2} \\ d=\sqrt[]{(7)^2+(0)^2} \\ d=\sqrt[]{49} \\ d=7\text{ units} \end{gathered}[/tex]

therefore

the distance DE is 7 units