The answer is 21 + 4x.
You find this answer by adding up all the sides.
9+12+4x= 21+4x ... you don't add 4x because it has a variable that we do not know of the value.
Find how far the car can travel on one gallon of gas, by dividing total miles by number of gallons:
105 miles / 7 gallons = 15 miles per gallon.
Now multiply that by the number of gallons to find total miles:
15 miles per gallon x 9 gallons = 135 total miles.
It suppose to be like 20.21
Can you retype this question in another form? like are you asking for the prime numbers?
