She will have $57 back because the ticket are buy one get one free and she has 7 friends so for 3 tickets that u buy 6 of your friend get to go and then thei is still one more friend so you have to buy one more ticket so 10.75*3=32.25
and 32.25+10.75=43 and 100-43=57
3x - y = 0 . . . (1)
5x + 2y = 22 . . . (2)
From (1), y = 3x . . . (3)
Putting (3) into (2) gives:
5x + 2(3x) = 22
5x + 6x = 22
11x = 22
x = 2
From (3), y = 3(11) = 33
x = 11, y = 33.
Presume y=kx +b,then substitute (3,0)&(5,4),
When x=3,y=0,so 3k+b=0;
When x=5,y=4,so 5k+b=4;
Now u can know that k=2,b=-6.
The answer is:y=2x-6.
The equation would be 40+15p=70+5p. You would subtract 5p from each side (15-5) and (5-5) and you'll have 40+10p=70. You would then subtract 40 from each side (70-40) and (40-40) to have 10p=30. You would divide by both of the sides by 10, you would end up with p=3. P is price training. The reason you divide and subtract on both sides is because you want the months to be on one side and the price training on the other side.