Answer:
2x +21
Step-by-step explanation:

21 3/16...as a decimal
the 21 is a whole number and goes to the left of the decimal....and the fraction 3/16 goes to the right of the decimal.
3/16 = 0.1875....now add ur 21 and u get 21.1875 inches wide
2 3/8....as a decimal
3/8 = 0.375....now put ur 2 in there and it becomes 2.375 inches thick
Hmm, the slope is undefined. But like what exactly are you looking for as an answer?
Your answer is d. hope this helps
That would be 2 numbers. they are 10 and -10.