Y2-y1 -5-(-8) 3
____ = _____ = ___ = -3/7
x2-x1 2-9 -7
Your equation should be
$4(40 tickets) + $5(X) = $400
160 +5x = 400
-160 -160
0 5x = 340
divide both sides by 5
5x/5 = 340/5
x = 68
so they need to sell 68 tickets at the door.
4(40) + 5(68) = 400
160 + 340 + 400
400 + 400
Keep in mind the the word "percent" translates to "for each 100." 25% can be read as "25 for each 100," which has the fractional representation
![\frac{25}{100}](https://tex.z-dn.net/?f=%20%5Cfrac%7B25%7D%7B100%7D%20)
and the decimal representation 0.25. All of these representations are just different ways of writing the same value.
Note too that the fraction
![\frac{25}{100}](https://tex.z-dn.net/?f=%20%5Cfrac%7B25%7D%7B100%7D%20)
can be reduced to
![\frac{1}{4}](https://tex.z-dn.net/?f=%20%5Cfrac%7B1%7D%7B4%7D%20)
, so what the question is really asking is: 1/4 of what number is 9?
Well, if we know that 1/4 of the number is 9, we can easily find how large the whole number is by finding all 4/4 of it (the <em>whole</em> number)<em /><em />, or 4 x 9, which multiplies out to
36.