okay for number 1, even though there isn’t a question to answer, my best guess would be H, 66 in^3. 
i multiplied the height (6) by the base (11) to get the 66.
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for number 2, here’s what you should do.
2x + 10 = 28
 - 10 -10 
(subtract 10 from both sides of the equal sign)
you should get..
2x = 18 
divide by 2 to get the x by itself..
x=9
and there u go! lmk if i helped u out babe