X = 7
5 + x can also be written as 5 + 7
5 + 7 = 12
X = (15 - 8y)/9
-5[(15 - 8y)/9] + 12y = -107
(-75/9) + (40/9) + 12y = -107
y = -8.59
x = [15 - 8(-8.59)]/9
x = 9.3
(x,y) = (9.3, -8.59)
All you have to do is write your question and someone will answer. For example, instead of writing "I do not understand how I find answers on here" you would ask something like what is 9*5? Then 2 people will see your question and answer. There are no pre-recorded answers, everything happens live. Hope this helps!
Here's what you have to do: multiply. 54.9×12= 658.8. So, he traveled 658.8 miles in twelve hours.