<h3>
Answer: cos(76)</h3>
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Explanation:
The original expression is of the pattern cos cos + sin sin. This pattern matches the second identity in the hint. Specifically, we'll say the following:
cos(A - B) = cos(A)cos(B) + sin(A)sin(B)
cos(A)cos(B) + sin(A)sin(B) = cos(A - B)
cos(94)cos(18) + sin(94)sin(18) = cos(94 - 18)
cos(94)cos(18) + sin(94)sin(18) = cos(76)
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We can verify this by use of a calculator. Make sure your calculator is in degree mode.
- cos(94)cos(18) + sin(94)sin(18) = 0.24192
- cos(76) = 0.24192
Both expressions give the same decimal approximation, so this helps confirm the two expressions are equal. You could also use the idea that if x = y, then x-y = 0. Through this method, you'll subtract the left and right hand sides and you should get (very close to) zero.
Should be C right? A rectangle demands that the diagonals are congruent
This can be solved by making an equivalent ratio.
The original ratio is what we know, 15 inches of wire for 90 cents.
In a ratio of inches of wire:cents, this would be 15:90.
Now for the equivalent ratio.
We don't know the number in the inches place but we do know it for the cents place.
Let's use x to represent inches of wire.
x:48 is our new ratio, and we need to find x.
Since x:48 and 15:90 are equivalent, that means the same thing that was done to 90 to get 48 has to be done to 15 to get the value of x, since the same thing must be applied to both sides.
We can find what 90 was divided by (which is what we'll have to divide 15 by) by dividing 90 by 48.
90 / 48 = 1.875
This means 48 • 1.875 = 90 and x • 1.875 = 15.
Since we don't know x though, we can isolate it by dividing both sides by 1.875.
x • 1.875 = 15
x • 1.875 / 1.875 = x
15 / 1.875 = 8
So x is 8.
Answer:
While you can be 15 inches of wire for 90 cents, you can buy 8 inches of wire for 48 cents at the same rate.
Hello, Marymack!
We know that in a geometric sequence defined by
and
, the sum can be calculated the following way:
