The answer would be, 20 inches, 12 inches in a foot multiplied by 4 feet equals 48 inches, now take 48 inches and multiply it by 28 inches which equals 1,344, then take 26,880 inches and divide it by 1,344 and your answer would be 20 inches. To check your answer the fourmula for volume for that object is, length x width x hight, so you take 48x28x20 and you get a volume of 26,880 inches. I hope that helped.
The answer should be 112 degrees
To solve for a variable, you need to get it (x) by itself.
x² - 14 + 31 = 63 Add 31 to -14
x² + 17 = 63 Subtract 17 from both sides of the equation
x² = 46 Square root both sides
x =

Check your work by plugging in

for x and then

.

² - 14 + 31 = 63 Square

46 - 14 + 31 = 63 Subtract 14 from 46
32 + 31 = 63 Add
63 = 63

² - 14 + 31 = 63 Square

46 - 14 + 31 = 63 Subtract 14 from 46
32 + 31 = 63 Add
63 = 63
So,
x is
and 
.