You know

Squaring both sides gives

Then raising both sides to any integer power
gives

That is, any power of
where the power is a multiple of 4 will always be equal to 1.
So

But perhaps you mean to write 20+1 as the exponent, in which case

Answer:
the angle x would still be the same when you dilate the same triangle. if x was 87 degree on the small triangle and then dilate it larger, the value of x would still be 87 degree.
Answer:
The value of ROE that will be exceeded by 78% of the firms is -1.77%.
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean
and standard deviation
the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
The mean ROE for the firms studied was 14.93% and the standard deviation was 21.74%. This means that 
What value of ROE will be exceeded by 78% of the firms?
This is the value of X when Z has a pvalue of 1-0.78 = 0.22.
This is 
So:




The value of ROE that will be exceeded by 78% of the firms is -1.77%.
You just need to substitute 4(2)-2(5)/2
8-10/2
8-5
=3