Which angle is complementary to DFE? Pls answer

<DFA

Step-by-step explanation:

When combined (<DFA and <DFE), they'll form 90 degrees which will make them complementary

Two angles are called complementary if their measures add to 90 degrees, and called supplementary if their measures add to 180 degrees. If two angles are complementary then they will add up to be 90, or inversely, if two angles add up to be 90, then they are complementary. If you know one acute angle, you can calculate its complementary angle by subtracting 90 and the angle. When the sum of two angles is equal to 90 degrees, they are called complementary angles. For example, 30 degrees and 60 degrees are complementary angles.

The complement of −135° is the angle that when added to −135° forms a right angle (90° ).

Step-by-step explanation:

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.