<h2>Answer</h2>
0.43
<h2>Explanation</h2>
Remember that 
Since the problem is telling us "Among tenth graders", we must focus on the 10th graders row only. From the row, we can infer that the frequency is the number of 10th graders who prefer going to sporting events, so
. Now, the sum of all frequencies will be the sum of all the 10th graders, so
. Let's replace the values:



And rounded to the nearest hundredth:

The answers are as follows:
1. Triangles are often used to build different types of support structures because of its beneficial properties. Triangles is rigid in shape and it has strength. When force is applied to the side of a triangle, it can not shift into another shape, this is because its sides and angles are fixed.
2. The properties of triangle that make it a desirable geometric shape for building support structures is its fixed sides, fixed angles, rigidity and strength. Triangles are the strongest shapes and they are stable. Thus, triangle can be easily fix together to provide strength and stability over a wide area.
3. There are different types of triangles, these include: equilateral triangle, scalene, isosceles, right triangle, obtuse and acute. Of all these triangles, the best triangle is equilateral triangle.
4. Triangle is preferred over other types of polygon because, it is the strongest. The other polygons can be bent into different other forms that are not regular polygon, but a triangle always retains its shape and can not be deformed.
Answer : The speed of both planes is 61.25 mph and 18.75 mph respectively.
Explanation:
Let the speed of first plane be x mph
Let the speed of second plane be y mph
Since we have given that difference of speeds is 80 mph
i.e. x - y= 80 (
1)
Distance between two planes = 3400 miles
As they are flying towards each other i.e. they are in the opposite direction.
So, Relative speed will be the sum of their speeds i.e.
Relative speed = x + y
And we know speed = 
Speed= 
⇒ Speed = 42.5 mph
Hence, Relative speed becomes 42.5 mph
⇒ x+y=42.5 (
2)
Now, by using the elimination method of solving the system of equation, we have ,
x= 61.25 mph
and y = 18.75 mph
Answer:
C.x2 + 12x + 4x + 48
Step-by-step explanation: