Question

A triangle has vertices T(-2,4), E(6,2), and D(1,-1). Is ATED a right triangle?

No, this is not a right triangle.
Yes, because ED is perpendicular to DT which makes a right angle.
Yes, because TE is perpendicular to DT which makes a right angle.
Yes, because TE is perpendicular to ED which makes a right angle.

Answer 1

• B. Yes, because ED is perpendicular to DT which makes a right angle.

Explanation:

Plot the given points and connect in pairs to get a triangle.

Visually we can say it is a right triangle as legs TD and ED seem perpendicular.

Let's confirm this by finding the slopes.

Slope of TD:

• m = (-1 - 4)/(1 -(-2)) = -5/3

Slope of ED:

• (-1 - 2)/ (1 - 6) = -3/-5 = 3/5

Product of the slopes is:

• -5/3*3/5 = -1

This confirms DT⊥ED

Correct choice is B