BC and EF have the opposite and reciprocal slopes.
According to the statement
we have given that the
Triangle ABC has been rotated 90° to create triangle DEF.
And we have to find the lines BC and EF have the opposite and reciprocal slopes.
So, For this purpose,
We know that the
Slope of a triangle represents the angle that are formed between positve X-axis moving anticlockwise towards y-axis.
And From triangle ABC
The slope of triangle ABC
AB = 4 and AC = 4 Then
slope of triangle = perpendicular / base
slope of triangle ABC = 4/4
so, it become tan45 degree which is 1.
So, Slope of BC is 1.
slope of triangle DEF = 4/-4
so, it become tan135 degree which is -1.
So, Slope of EF is -1.
Slope of ABC is 1, where as
Slope of DEF is -1
∴ BC and EF have the opposite and reciprocal slopes.
Learn more about the slopes here
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