Yeah his answer is correct Good job!
Answer:
Step-by-step explanation:
Believe it or not, the two areas are the same.
The base of the rectangle is PQ
The height of the rectangle is PS
Now look at the parallelogram.
The base is PQ
The height is PS
The area has to be the same in both cases. There is no other way to interpret what is happening.
<1=97°
steps:
<1+83=180 co interior angle
<1=180-83=97°
I assume you're supposed to establish the identity,
cos(A) cos(2A) cos(4A) = 1/8 sin(8A) / sin(A)
Recall the double angle identity for sine:
sin(2<em>x</em>) = 2 sin(<em>x</em>) cos(<em>x</em>)
Then you have
sin(8A) = 2 sin(4A) cos(4A)
sin(8A) = 4 sin(2A) cos(2A) cos(4A)
sin(8A) = 8 sin(A) cos(A) cos(2A) cos(4A)
==> sin(8A)/(8 sin(A)) = cos(A) cos(2A) cos(4A)
as required.
One liter is 1,000 ml. plus 299 ml. is 1,299 ml. plus the additonal 398 ml. is 1,697 ml. which is 722 ml. less than the total volume. (722 ml. of water can still be added.)