Answer:
x= 7.87298334621 x=.12701665379
Step-by-step explanation:
This is in standard form so we have to factor this into
x^2-8x + 16 + 1 = 16
(x-4)^2 = 15
(x-4) =
x-4= ± 3.87298334621
x-4 = 3.87298334621 x-4= -3.87298334621
x= 7.87298334621 x=.12701665379
Odd numbers take the form , where
is an integer. When
, the last odd number would be 799. So we're adding
By reversing the order of terms, we have
and we can pair up terms in both sums at the same position to write
so that we are basically adding 400 copies of 800, and from there we can find the value of the sum right away:
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We could also make use of the formulas,
We have
Answer: Choice A. sin(A) = cos(B)
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Explanation:
The rule is that sin(A) = cos(B) if and only if A+B = 90.
Note how
Since both result in the same fraction BC/AB, this helps us see why sin(A) = cos(B). Similarly, we can find that cos(A) = sin(B).
In the diagram below, the angles A and B are complementary, meaning they add to 90 degrees. So this trick only applies to right triangles.
The side lengths can be anything you want, as long as you're dealing with a right triangle.
