Her total should be 84. You have your 30 dollars that will not change which you need to add to the amount of every visit. To find the amount for each time she went you have to do 3*18 because she went 18 times for 3 dollars each. Your answer to 3*18 should be 54. You now have to add those 54 to the 30 per month. 30+54. That should be 84
Answer:
-2x+3y =1.......(1)
y=3x-9........(2)
Now,
putting the value of y in equation (1),
-2x+3(3x-9)=1
or,-2x+9x-27=1
or,7x-27=1
or,7x=28
x= 4
Now putting the value of X in equation (2),
y=3×4-9
= 12-9
=3
(x,y)=(4,3)
