Answer:
17F
Step-by-step explanation:
(-2F) +(19F) = 17F
The signed numbers add in the usual way. (If you really can't do this in your head, a calculator can help.)
I think it may be true, please correct me if i am wrong
Answer:

Step-by-step explanation:
![Volume\:of\:cube:V=a^{3} \:(a\:is\:the\:length\:of\:each\:edge)\\\Leftrightarrow a=\sqrt[3]{V} \Leftrightarrow a=\sqrt[3]{729} =9](https://tex.z-dn.net/?f=Volume%5C%3Aof%5C%3Acube%3AV%3Da%5E%7B3%7D%20%5C%3A%28a%5C%3Ais%5C%3Athe%5C%3Alength%5C%3Aof%5C%3Aeach%5C%3Aedge%29%5C%5C%5CLeftrightarrow%20a%3D%5Csqrt%5B3%5D%7BV%7D%20%5CLeftrightarrow%20a%3D%5Csqrt%5B3%5D%7B729%7D%20%3D9)
Answer:
28
Step-by-step explanation:
Since the triangle is a right triangle, we can use SOH CAH TOA to find ?. 10 is OPPOSITE to ? and 21 is HYPOTENUSE to ?, so we can use SIN to find ?.
SIN(?) = 10/21
? = ARCSIN(10/21)
? = 28.437