Answer:
75 minutes or 1 hr and 15 minutes
Step-by-step explanation:
for history, he studied 2 hrs and 40 minutes....thats a total of 160 minutes
this is 10 minutes more then twice the time he spent on his last exam.
let x represent the time spent on last exam
160 = 2x + 10
160 - 10 = 2x
150 = 2x
150/2 = x
75 = x.......so he spent 75 minutes (or 1 hr and 15 minutes) on his last exam
It should be y=x Good luck!
<span>c. a statement cannot become a theorem until it is proven...
Hope it helps !!!</span>
Answer:

Step-by-step explanation:
Given


Required
Solve
Substitute 9 for x in 


Remove bracket




Simplify fraction
