I think 4 most likely because if u take the middle of the 3 dots it would lave the last dot on the 4
84 to 62. You have to subtract 146-84 to get the number of girls from the class.
The answer is: The first triangle. The reasons are shown below:
1. All the triangles are rigth triangles, because they have an angle of 90°. So, let's calculate the others angles of the first one:
Tan(α)^-1= opposite leg/adjacent leg
Opposite leg=5
Adjacent leg=5√3
Tan(α)^-1= 5/5√3
Tan(α)^-1=30°
2. Let's calculate the other angle:
Tan(α)^-1= opposite leg/adjacent leg
Now, the opposite leg will be 5√3 and the adjacent leg will be 5. Then:
Tan(α)^-1= 5√3/5
Tan(α)^-1=60°
As you can see, the angles of first triangle are: 30°,60° and 90°.
143 x 2 = 286 because if you mulitpy each by 2 you get 286
Answer:
Area: (3+√7) x (1+2√7) = 17+7√7 = 35.52
Perimeter: 2(3+√7) + 2(1+2√7) = 8+6√7 = 23.87