Answer:
A: 10 x 1/2 = 15
Step-by-step explanation:
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You can use the sum and difference identities which for cosine is cos(a+b)= cosacosb-sinasinb
Answer:

Step-by-step explanation:



or

Answer: xy=11 in.; yz= 13 in.; xz=13in.
Step-by-step explanation:
i’m pretty sure that’s it
You can make 4 out of 18 cubes