Answer:'
-9.7 minus, in 13
Step-by-step explanation:
Answer:
Hence, the perimeter of the triangles are:
P=123.2727 dm
P'=102.7272 dm
Step-by-step explanation:
In two similar triangles:
The ratio of the areas of two triangle is equal to the square of their perimeters.
Let A and A' represents the area of two triangles and P and P' represents their perimeter.
Then they are related as:

We are given:
A=72 dm^2 , A'=50 dm^2
and P+P'=226 dm.-----------(1)
i.e. 
on taking square root on both the side we get:

Now putting the value of P in equation (1) we obtain:

Hence,
P=226-102.7272=123.2727
Hence, the perimeter of the triangles are:
P=123.2727 dm
P'=102.7272 dm
Answer:
That would be sina.
Step-by-step explanation:
sin(a+b) = sinacosb + cosasinb
sin(a-b) = sinacosb - cosasinb
Adding we get sin(a+b) + sin(a-b) = 2sinaccosb
so sinacosb = 1/2sin(a+b) + sin(a-b)
Okay I'm not too sure on this but I believe it is the third one.
I hope this helps!!