x is the number of $1 increase in the price.
If there is no increase, then the total money earned is
2 × 70 = 140
If there is $1 increase, then the total money earned is
(2 + 1) × [70 - 8(1)]
If there is $2 increase, then the total money earned is
(2 + 2) × [70 - 8(2)]
If we continue the pattern, for x times $1 increase, total money earned is
(2 + x)(70 - 8x) =
![-8x^(2) +54x+140](https://img.qammunity.org/2019/formulas/mathematics/middle-school/z1bh5sthydusbrh3i3cuc6lrowhyt0h48z.png)
If we substitute x = 0 in the above equation, we will get
the total money earned = $140.
It means if there is no increase, then the total money earned = 140.
Hence, 140 is the constant term and it represents that there is no increase in price.