Answer:
Step-by-step explanation:
Two of the legs will be at right angles to each other and have negative reciprocal slopes. Area will be half of the product of these two legs.
slope of DE (-3 - (-1)) / (1 - (-6)) = -2/7
slope of EF (4 - (-3)) / (3 - 1) = 7/2
so these two are perpendicular
check the DF line to be certain
slope of DF (4 - (-1)) / (3 - (-6)) = 5/9
Length of DE = √(-2² + 7²) = √53
Length of EF = √(7² + 2²) = √53
Area of triangle
A = ½√53√53 = 26.5 units²
