7.84/7 = $1.12
5.70/5 = $1.14
1.14 - 1.12 = .2
2 cents cheaper
Well first, you have to know the distance formula. You plug the coordinates into it and you get the answer.
√1² + -7² = d
d = 7.1
Let x= number rows
Then x + 5 = number of seats per row
x(x+5) = 126
X^2 + 5x = 126
x^2 + 5x -126 = 0; now factor or use quadratic:
(x+14)(x-9) = 0; so the answers are either -14, or 9, and since -14 is not possible in this case because you can't have a negative number of rows, the answer is 9 rows.
Check work: number of rows = 9, number of seats per row = 9+ 5= 14, and 9 x 14 = 126
There are two variables here, which are time (minutes) and the number of beats, and they both have a relationship (68 beats in one minute), therefore it is an example of a unit rate
