Answer:
C. 
Step-by-step explanation:
We have been given a triangle. We are asked to find the measure of angle Z using Law of cosines.
Law of cosines: 
, where, a, b and c are sides opposite to angles A, B and C respectively.
Upon substituting our given values in law of cosines, we will get:
Now, we will use inverse cosine or arc-cos to solve for angle Z as:
Therefore, the measure of angle Z is approximately 51 degrees.
Answer: Choice B) {3, 5, sqrt(34)}
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Explanation:
We can only have a right triangle if and only if a^2+b^2 = c^2 is a true equation. The 'c' is the longest side, aka hypotenuse. The legs 'a' and 'b' can be in any order you want.
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For choice A,
a = 2
b = 3
c = sqrt(10)
So,
a^2+b^2 = 2^2+3^2 = 4+9 = 13
but
c^2 = (sqrt(10))^2 = 10
which is not equal to 13 from above. Cross choice A off the list.
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Checking choice B
a = 3
b = 5
c = sqrt(34)
Square each equation
a^2 = 3^2 = 9
b^2 = 5^2 = 25
c^2 = (sqrt(34))^2 = 34
We can see that
a^2+b^2 = 9+25 = 34
which is exactly equal to c^2 above. This confirms the answer.
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Let's check choice C
a = 5, b = 8, c = 12
a^2 = 25, b^2 = 64, c^2 = 144
So,
a^2+b^2 = c^2
25+64 = 144
89 = 144
which is a false equation allowing us to cross choice C off the list.
So since 2/5 of the washing machines have been sold that means 3/5 remain in the store
first find the number of washing machines that were in the store before any were sold
X is the number of washing machines in the store before selling
18=(3/5)X
18/(3/5)=X
X=18*(5/3)
X=30
so at the beginning there were 30 machines
then multiply the percent sold (2/5) by the number at beginning to find the number sold
(2/5)*30=12
so 12 machines were sold
to find the cost per machine divide the total price by number of machines sold so
$3840/12= $320
so the answer is $320 per machine
Answer:
The location of the point is between Quadrant II and Quadrant III
Step-by-step explanation:
we know that
The abscissa refers to the x-axis and ordinate refers to the y-axis
so
in this problem we have
the coordinates of the point are 
see the attached figure to better understand the problem
The location of the point is between Quadrant II and Quadrant III
