Write out the sum formula for sin
<span>sin(x + y) = sinxcos + sinycosx </span>
<span>Then expand sin(a + b) + sin(a - b) </span>
<span>sinacosb + sinbcosa + sinacosb - sinbcosa </span>
<span>The 2nd and 4th terms cancel and you get </span>
<span>2sinacosb</span>
The solution is: 252. 14x18
(D) hope this helps kxjdndldjdkwpwnx
Wouldn't it be. 8 pieces because you cut each sides into two pieces so like this. —|—. You'll end up having four square pieces, but count the pieces that creates an L shape.
best wishes good luck
Answer:
Imagine that the number that we are looking for is x
We know that:
x/5 - 78 = 9
x/5 = 9 + 78
x/5 = 87
x = 87 . 5 = 435
So the number we need is 435