Answer:
Law of cosines to find missing measures
c^2= a^2+ b^2 - 2ab*cos(C)
Used because it is a SAS triangle
Step-by-step explanation:
This is known as a side, angle, side, or SAS triangle. We can find the missing measures by using the Law of cosines
c^2= a^2+b^2-2ab*cos(C)
Answer:
x is 42
X = 42
Step-by-step explanation:
Answer:
20
Step-by-step explanation:
a^2 + b^2 = c^2
12^2 + 16^2 = c^2
144 + 256 = c^2
400 = c^2
20 = c
The length of BC = 20
Answer: For Ryan to get an average of exactly 91, she needs to get a 90 on her fifth quiz.
Step-by-step explanation:
You can find the average of a set of numbers by adding them together and dividing the sum by the amount of numbers added.
Ryan has five total quizzes. Only four of them are known, so we can represent her fifth quiz as X.
, dividing the five quizzes' sum by 5
She wants the average to be exactly 91, so you can set the expression equal to 91 and solve:

For Ryan to get an average of exactly 91, she needs to get a 90 on her fifth quiz.
8 - 7a = - 6a + 9
a = - 1
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