If triangle ABC is equal to triangle def, angle a = 40 degrees, angle e = 70 degrees, BC = a, ab = B, then DF =? The length of DF is

Angle a = angle d = 40 degrees, angle e = angle B = 70 degrees, so angle c = angle f = 70 degrees. Angle c = angle B, so AB = AC = de = DF = B

Delta ABC ∽ def and triangle ABC are similar to triangle def. Is there any difference
The classmate said there was a difference, but her notes were slightly written. I don't think there was a difference. By the way, how could there be a difference?

There is a difference
When △ ABC ∽ DEF is used, the corresponding vertex is a to D, B to e, C to F
When ABC is similar to def, only two triangles are similar, and the vertex indicated by the letter of corresponding position is not necessarily corresponding

In △ ABC and △ def, ∠ a = ∠ d = 80 °, B = 55 °, e = 45 °, are these two triangles similar

In Δ ABC, ∠ C = 180 ° - A - ∠ B = 45 °
In Δ def, ∠ f = 180 ° - D - E = 55 °
∵∠A=∠D=80°,∠B=∠F=55°,∠C=∠E=45°
∴△ABC∽△DEF

In △ ABC, ∠ a = ∠ B = half ∠ C, calculate the degree of three internal angles

∠A+∠B+∠C=180
0.5∠C+0.5∠C+∠C=180
∠ C = 90 degrees
Then ∠ a = ∠ B = 45 degrees

In known triangle ABC, angle a = angle B = one third angle c, try to find the degree of angle C

Angle a = angle B = one third angle c
Because angle a + angle B + angle c = 180 degrees
So the third angle c + the third angle c + C = 180 degrees
Five thirds angle c = 180 degrees
Angle c = 180 degrees △ 5 / 3 = 108 degrees

In △ ABC, it is known that ∠ a = 13 ∠ B = 15 ∠ C, and the degrees of ∠ a, ∠ B, ∠ C are calculated

The results show that ∵ a = 13 ∵ B = 15 ∵ C, ∵ B = 3 ∵ a, ∵ C = 5 ∵ a, ∵ a + ∵ B + ∵ C = 180 ° and ∵ a + 3 ∵ a + 5

If triangle ABC is equal to triangle def, angle a = 40 degrees, angle e = 70 degrees, BC = a, ab = B, then DF =? The length of DF is