In the triangle ABC, the area of BDE, DCE and ACD are 90, 30 and 28 square centimeters respectively?

Because s △ BDE = 90 square centimeter, s △ DCE = 30 square centimeter, be: EC = 90:30 = 3:1, and s △ ABC = 90 + 30 + 28 = 148 square centimeter, the area of triangle Abe is 148 × 33 + 1 = 111 (square centimeter), and the area of triangle ade is 111-90 = 21 (square centimeter). A: the area product of triangle ade is 21 square centimeter

RELATED INFORMATIONS

1. Given that the points D and E are on the sides AB and AC of △ ABC, de / / BC, the area of △ ABC is s, BC = a, and the area of △ ade is S1, the length of De can be obtained (expressed in the algebraic form of the letters s, S1 and a) A D E B C
2. Given that points D and E are on edges AB and AC of △ ABC, de / / BC, the area of △ ABC is s, BC = a, and the area of △ ade is S1, the length of De can be obtained It is represented by the algebraic expression of the letters s, S1 and a
3. In the acute triangle ABC, be is perpendicular to AC, D is the upper point of AB, angle ade = angle c, s triangle ade area is S1, and △ ABC area is S2, then S1 / S2 is
4. If the three sides of a triangle form an arithmetic sequence, the circumference is 36 and the circumference of the inscribed circle is 6 π, then the triangle is a triangle
5. A and B are walking in opposite directions in AB and meet each other in 2 hours. It is known that the speed ratio of a and B is 5:4, so how long can a catch up with B when they are walking in the same direction?
6. The original tonnage ratio of a and B piles of coal is 5:3. If 90 tons are transported from a pile to B pile, then the tonnage of the two piles is equal. How many tons are there in a and B piles?
7. Is the 2.8 ton truck a large truck or a small truck
8. A and B set out from a and B at the same time. The speed ratio of a and B is 7:5. If they walk in opposite directions, they will meet in 0.5 hours If you go in the same direction from a to B, how many hours does it take for a to catch up with B?
9. There are two baskets of apples. The first basket is 1.2 times of the second basket. Take 2.4 kg from the first basket to the second basket. The two baskets are equal in weight. How many kg are there in the first and second baskets?
10. If the speed of a car from a to B is increased by 20%, it can arrive ahead of time; if it runs at the original speed for 100, it happens that You can also arrive at the same time in advance. How many kilometers are there between a and B?
11. In the tetrahedral PABC, PA = Pb = PC = 2, APB = BPC = APC = 30 degree In the tetrahedral PABC (P is the vertex), PA = Pb = PC = 2, ∠ APB = ∠ BPC = ∠ APC = 30 °, starting from point a, circling along the tetrahedral surface, and then returning to point a, the shortest distance is
12. In RT △ ABC, ∠ ACB = 90 °, ∠ BAC = 30 °, BC = 1, P is a point in △ ABC, and ∠ APC = ∠ BPC = ∠ APB = 120, calculate the value of PA + Pb + PC
13. Equilateral triangle ABC, P is a point in the triangle, PA is equal to 3, Pb is equal to 5, PC is equal to 4, find the degree of ∠ APC
14. P is any point in the equilateral triangle ABC, PA = 3, Pb = 5, PC = 4, find the angle APC
15. As shown in the figure, it is known that P is a point on the side BC of △ ABC, and PC = 2PB. If ∠ ABC = 45 ° and ∠ APC = 60 °, find the size of ∠ ACB
16. In △ ABC, the angle ABC = 90, ad is the angular bisector, the points E F are on AC ad, and AE = AB EF / / BC prove that bdef is a diamond
17. It is known that AB is parallel to EF, CD, ad is parallel to BC, and BD is bisected
18. As shown in the figure, in △ ABC, ab = AC, e is on AC, and the extension line of ad = AE, de intersects BC at point F
19. As shown in the figure, extend the edge BC of △ ABC to d so that CD = BC, take the midpoint F of AB and the edge DF intersect AC with E, and calculate the value of aeac
20. As shown in the figure, in RT △ ABC, if ∠ C = 90 °, a = 30 °, e is the point on AB, AE: EB = 4:1, EF ⊥ AC is in F, and FB is connected, then the value of Tan ⊥ CFB is equal to () A. 33B. 233C. 533D. 53