Answer:
7. A = 40.8 deg; B = 60.6 deg; C = 78.6 deg
8. A = 20.7 deg; B = 127.2 deg; C = 32.1 deg
Step-by-step explanation:
Law of Cosines

You know the lengths of the sides, so you know a, b, and c. You can use the law of cosines to find C, the measure of angle C.
Then you can use the law of cosines again for each of the other angles. An easier way to solve for angles A and B is, after solving for C with the law of cosines, solve for either A or B with the law of sines and solve for the last angle by the fact that the sum of the measures of the angles of a triangle is 180 deg.
7.
We use the law of cosines to find C.






Now we use the law of sines to find angle A.
Law of Sines

We know c and C. We can solve for a.


Cross multiply.





To find B, we use
m<A + m<B + m<C = 180
40.8 + m<B + 78.6 = 180
m<B = 60.6 deg
8.
I'll use the law of cosines 3 times here to solve for all the angles.
Law of Cosines



Find angle A:





Find angle B:





Find angle C:





It’s Seven Hundred Thirteen point forty-nine
Surface area = area of 3 rectangles + 2 triangles
= 3*(3*7) + 2 * ( 1/2 * 3 * 2.6)
= 63 + 2* 3.9
= 70.8 in^2
Answer: 3a+6a+6+6
Step-by-step explanation:
Let g be the number of grandchildren, and d be the number of dogs. They both have only one head, so the number of heads is

Grandchildren have 2 legs, while dogs have 4. So, the total number of legs is

From the first equation (the one for the heads) we can derive

Substitute this into the second to get

So, there are 9 dogs and (from the first equation
