Answer: 6
Step-by-step explanation:
(41--1)/ (8-1) = 42/7 = 6
Answer:
The required result is proved with the help of angle bisector theorem.
Step-by-step explanation:
Given △ABD and △CBD, AE and CE are the angle bisectors. we have to prove that 
Angle bisector theorem states that an angle bisector of an angle of a Δ divides the opposite side in two segments that are proportional to the other two sides of triangle.
In ΔADB, AE is the angle bisector
∴ the ratio of the length of side DE to length BE is equal to the ratio of the line segment AD to the line segment AB.
→ (1)
In ΔDCB, CE is the angle bisector
∴ the ratio of the length of side DE to length BE is equal to the ratio of the line segment CD to the line segment CB.
→ (2)
From equation (1) and (2), we get
Hence Proved.
Answer:
A. T > 2.539
Step-by-step explanation:
We have a hypothesis test of the mean, with unknown population standard deviation.
The hypothesis are:

From the hypothesis we can see that the test is right-tailed, so the critical value of t should be a positive value.
The degrees of freedom can be calculated as:

The significance level is 0.01, so the critical value tc should be the one that satisfies:

Looking up in a t-table, for 19 degrees of freedom, this critical value is tc=2.539.
If the ball hit the ground it means that its height is equal to 0. In order to find the time after the ball <span>will hit the ground, we need to find the solution of the equation h(x)=0 which is different to 0.
-4.9x^2+21.3x=0
x(-4.9x+21.3)=0
-4.9x+21.3=0
x=21.3/4.9 = 4.3469 seconds</span>