Answer: 14gallons
Step-by-step explanation:
12gallons/144miles = 1gallon/12miles
Therefore 6gallons = 12*6 = 72miles.
In order to cover 240miles, she will need 240/12 = 20gallons.
20-6 = 14gallons
She will need 14gallons of gas more.
Your answer is c i pretty insurance
Using elimination method to find y
3x - 4y = -15 (multiply 4)
4x + 3y = 5 (multiply 3)
------------------------------------
12x - 16y = -60
12x + 9y = 15
--------------------- - (substract)
-25y = -75
y = 3
Using subtitution method to find x
3x - 4y = -15
3x - 4(3) = -15
3x - 12 = -15
3x = -3
x = -1
The solution (-1,3)