Answer:

Step-by-step explanation:
The window consists of a large square and 4 smaller triangles on the outside. The side length of this square is marked as 10, and therefore the area of this square is
.
The area of a triangle is given by
. Since the problem states that the overlapping squares are congruent, both legs of the triangle will be
and intersect at a
angle.
Thus, the sum of all four triangles is
.
Therefore, the area of the window is:

Answer:
Cos b
Step-by-step explanation:
1/2[sin(a+b)+sin(a-b)]
1/2[sin a cos b +cos a sin b + sin A cos B - cos A sin B]
1/2[2sin a cos b]
sin a cos b
Answer:
D
Step-by-step explanation:
A plausible guess might be that the sequence is formed by a degree-4* polynomial,

From the given known values of the sequence, we have

Solving the system yields coefficients

so that the n-th term in the sequence might be

Then the next few terms in the sequence could very well be

It would be much easier to confirm this had the given sequence provided just one more term...
* Why degree-4? This rests on the assumption that the higher-order forward differences of
eventually form a constant sequence. But we only have enough information to find one term in the sequence of 4th-order differences. Denote the k-th-order forward differences of
by
. Then
• 1st-order differences:

• 2nd-order differences:

• 3rd-order differences:

• 4th-order differences:

From here I made the assumption that
is the constant sequence {15, 15, 15, …}. This implies
forms an arithmetic/linear sequence, which implies
forms a quadratic sequence, and so on up
forming a quartic sequence. Then we can use the method of undetermined coefficients to find it.
Answer:308? Good luck
Step-by-step explanation: