Answer:
Gọi AH là đường cao kẻ từ A đến BC
Xét tam giác AHC vuông tại H
Suy ra AH = HC. cotA= 9.cot35° = 12,9
Xét tam giác AHB vuông tại H
Suy ra BH = AH.tanA = 12,9.tan61°=23,37
Ta có BC= HC+ HB= 9+23,27 =32,27
Diện tích tam giác ABC = 1/2 × AH ×BC= 1/2 ×12,9×32,27=208,1415
Answer:
2/13
Step-by-step explanation:
In a regular deck of cards, there are a total of 52 cards. Of these, there are 4 8's and 4 jacks, making a total of 8 "desirable" outcomes. Therefore, the probability is 8/52=2/13. Hope this helps!
The discriminant is the part of the quadratic formula underneath the square root symbol: b²-4ac. The discriminant tells us whether there are two solutions, one solution, or no solutions.
Step-by-step explanation:
15t + 30 = 20t | -15t
30 = 5t
t = 30/5 = 6
20 + 5t = -6t + 86 | + 6t
20 + 11t = 86 | -20
11t = 66
t = 6
18t + 20 = 24t + 50 | -18t
20 = 6t + 50 | -50
-30 = 6t
t = -30/6 = -5
18t - 2 = 10t + 54 | -10t
8t - 2 = 54 | +2
8t = 56
t = 56/8 = 7
7t - 5 = 15t + 91 | -7t
-5 = 8t + 91 | -91
-96 = 8t
t = -96/8 = -12
