As shown in the figure, the elevation angle of C is ∠ CAD = 30 ° from a, the elevation angle of C is ∠ CBD = 45 ° from B, and the angle of view is ∠ ACB when measuring a and B from C=______ Degree

As shown in the figure, the elevation angle of C is ∠ CAD = 30 ° from a, the elevation angle of C is ∠ CBD = 45 ° from B, and the angle of view is ∠ ACB when measuring a and B from C=______ Degree

Method 1: ∵ - CBD is the outer angle of △ ABC, ∵ - CBD = ∵ CAD + ∵ ACB, ∵ - ACB = ∵ CBD - ∵ ACB = 45 ° - 30 ° = 15 °. Method 2: from the definition of adjacent complementary angle, ∵ - CBD = 180 ° - 45 ° = 135 °. ∵ - CAD = 30 °, ∵ CBA = 135 °, ∵ - ACB = 180 ° - CAD - ∵ CBA = 180 ° - 30 ° - 135 ° = 180 ° - 165 ° = 15 °

As shown in the figure, the elevation angle of C is ∠ CAD = 30 ° from a, the elevation angle of C is ∠ CBD = 45 ° from B, and the angle of view is ∠ ACB when measuring a and B from C=______ Degree

Method 1: ∵ CBD is the outer angle of △ ABC, ∵ CBD = ∵ CAD + ∵ ACB, ∵ ACB = ∵ CBD - ∵ ACB = 45 ° - 30 ° = 15 °. Method 2: from the definition of adjacent complementary angle, ∵ CBA = 180 ° - CBD = 180 ° - 45 ° = 135 °. ∵ CAD = 30 °, ∵ CBA = 135 °, ∵ ACB = 180 ° - CAD - ∵ CBA =

How to draw a CAD circle into a sector?
It's just like a household bucket. The top is big and the bottom is small. How to operate in CAD drawing? I'll draw a cutting sector diagram,

This needs to be calculated. First, calculate the radius of the sector circle, and then draw the arc according to the center of the circle and the arc length of the starting point

As shown in the figure, in the RT triangle ABC, the angles C = 90 °, D and E are on AC and ab respectively, and the angle ade = angle B. what is the shape of the triangle ade? Why?

A right triangle, similar to ABC, has two angles at the same angle