Total: 318
Student tickets: x
Adult tickets: 3x+6
x+(3x+6)=318 -> 4x+6=318 -> 4x=312 -> x=78
3(78)+6 = 234+6 = 240
240 adult tickets were sold
The storage tank one is 14.99
Half cylinder is 471.239
I don't remember how to do the second one sorry :(
-8x+9y=23 -- y=8/9x+23/9
(-4,-1), (1/2,3)
(3--1)/(1/2--4)= 4/(4 1/2)=.888888889
So answer A because if you rearrange it in y=mx+b form you see it's y=8/9x+23/9. And using the two points provided you can subtract to find the slope which comes out to be 8/9 the only two answers with that are A and B, so eliminate C and D. Then you can easily tell by looking at the graph that the y-intercept is positive, thus answer A is the only answer that works.
First, how much were her songs? It's two songs each, and their separate prize was 0.99:
total prize was 2*0.99=1.98
this gets added to the membership prize:
19.99+1.98=21.97
you can also calculate this by rounding all the numbers (20+1+1) and substracting the amount you rounded (three times one cent) - the result would be the same.