Answer:
angle 1 and angle 3 are congruent
Step-by-step explanation:
Angles supplementary to the same angle are congruent. Here both angles 1 and 3 are supplementary to angle 2, so angles 1 and 3 are congruent.
_____
If you like, you can get there algebraically:
m∠1 + m∠2 = 180
m∠3 + m∠2 = 180
Subtract the second equation from the first:
(m∠1 + m∠2) - (m∠3 + m∠2) = (180) - (180)
m∠1 -m∠3 = 0 . . . . simplify
m∠1 = m∠3 . . . . . . add m∠3
When angle measures are the same, the angles are congruent.
∠1 ≅ ∠3
Answer:
Step-by-step explanation:
AE is 9. ED is 6. The triangle ABE is proportional to ACD, so their sides are proportional. For example, AE:ED = AB:BC. So, ED/AE = 2/3 = BC/AB. This gives us 2/3 = x/10, which gives us x=6.6667
Given the dataset

We start by computing the average:

We compute the difference bewteen each element and the average:

We square those differences:

And take the average of those squared differences: we sum them

And we divide by the number of elements:

Finally, we take the square root of this quantity and we have the standard deviation:

By using distributive property we get
5(2)+5(7)
Therefore you answer is D. 5(2)+5(7)