If the train travels 744 miles in 3 hours then to determine the unit rate the train is traveling per hour you have to divide the miles by the hours, in this case (744 miles)/(3 hours). The final result concludes as 248 miles per hour.
Step one: set the base of each term to be the same (10)
(10ˣ)(10²)²ˣ = (10³)⁵
(10ˣ) (10⁴ˣ)= (10¹⁵)
10⁵ˣ = 10¹⁵
Because the indices are the same we can equate the two.
5x = 15
x = 3
Check 10⁵ˣ³ = 10¹⁵ 10¹⁵=10¹⁵