A trapezoid is a polygon of four sides with two parallel sides.
The area of trapezoid is the half sum of the lengths of the paralled sides times the height which is the distance between the parallel sides.
Call b1 and b2 the lengths of the two parallel sides and H the heigth, the formula is [1/2](b1 + b2) H.
We know b1 = 12cm, b2 = 12cm + 2 cm, and the area = 39 cm^2, then we can find H:
39 = [1/2](12 + 14)*H
39 = (13/2)H => H = 2*39 / 13 = 6 cm
Answer: 6 cm
Answer: D
I hope this helps.
Answer:
It took her two hours
Step-by-step explanation:
100 miles divided by 50mph =2 hours
hope it helps!
Answer:
The standard error of the mean is 0.0783.
Step-by-step explanation:
The Central Limit Theorem helps us find the standard error of the mean:
The Central Limit Theorem estabilishes that, for a random variable X, with mean and standard deviation , a large sample size can be approximated to a normal distribution with mean and standard deviation .
The standard deviation of the sample is the same as the standard error of the mean. So
In this problem, we have that:
So
The standard error of the mean is 0.0783.
You can tell when you cant draw an even L shaped figure at the intersects of the bottom and the side. 90 degrees. But there are many different ways that may make more sense. Happy to help:)