An obtuse triangle would be formed. If you add all the angles, you get a total of more then 180 causing it to b obtuse.
Whenever you see the word "per" you can ALWAYS substitue in the word "divide". When you see "miles per gallon", change "per" into "divided by" to get miles divided by gallons. That is how you will solve the problem.
SO.....
300 miles ÷ 10 gallons = 30 miles per gallon
Angle 1 and angle 5 are equal so you can set the equations equal to each other. 60 - 2x = 70 - 4x
60 + 2x = 70
2x = 10
x= 5