Yes, your work is correct.
The diagram does illustrate x²+6x+9=72. This is also represented by
(x+3)² = 72
We can take the square root of both sides:

When we evaluate this, the answers are x = -11.5 or x = 5.5.
The answer is 91 because the tens place has to be 8 more so in the 80's, 8 would be 8 more than 0 and 0 is not one of the digits and it's a 2 digit number so it can't go to the 100's so 91 is the best answer. I hope this helped you
Find how fast it travels in one hour:
460 miles / 2 hours = 230 miles per hour.
A) Multiply the speed per hour by the number of hours:
230 x 8 = 1840 miles in 8 hours.
B) 230 x 20 = 4,600 miles in 20 hours.
C) 460 miles / 2 hours = 230 miles per hour.