As shown in the figure below, a is the midpoint on the de side of the triangle CDE, BC is equal to two-thirds of CD, if the area of the triangle ABC (shadow part) is 10 square centimeters, find three Area of angular abd and triangular ace?

As shown in the figure below, a is the midpoint on the de side of the triangle CDE, BC is equal to two-thirds of CD, if the area of the triangle ABC (shadow part) is 10 square centimeters, find three Area of angular abd and triangular ace?

Draw a picture by ourselves. We can see from the picture that the height of triangle abd is the same as that of triangle ABC, BC is equal to two-thirds of CD. We can get that CD is equal to 3bd, BC = 2bd. If the area of triangle ABC (shadow part) is 10 square centimeters, the area of abd is half of that of ABC (the height is the same, and the bottom is the relationship between two times). Similarly, the height of triangle ace and ACD is the same, A is the midpoint of the de side of the triangle CDE, so ad = AE, that is, the bottom is the same, so the area of ACE and ACD of the triangle is the same. ACD = 10 + 5 = 15, so the area of ace of the triangle is also 15

In the figure below, the area of triangle ABC is 30 square centimeters, D is the midpoint of BC, AE is twice as long as ED, so what is the area of triangle CDE
30 minutes fast

Because the length of AE is twice that of ED, the height of triangle CDE is 1 / 3 of that of triangle ABC, and CD = 1 / 2 * BC, so the area of triangle CDE is 1 / 6 * 30 = 5