To tell if an equation has infinite solutions, the equation will be equal to each other.
For example,
x = x
x + 1 = x + 1
x - y = x - y
And so on...
And in special cases,
0x = 0
0x = 0(y + 1)
They have infinite solutions because there's no constant to determine the variable.
T = 5, so after 5 years
p(t) = t^3 - 14t^2 + 20t + 120
Take derivative to find minimum:
p’(t) = 3t^2 - 28t + 10
Factor to solve for t:
p’(t) = (3t - 2)(t - 5)
0 = (3t - 2)(t - 5)
0 = 3t - 2
2 = 3t
2/3 = t
Plug 2/3 into original equation, this is a maximum. We want the minimum:
0 = t - 5
5 = t
Plug back into original:
5^3 - 14(5)^2 + 20(5) + 120
125 - 14(25) + 100 + 120
125 - 350 + 220
- 225 + 220
p(5) = -5
Total = 16
Graduates = 4



Rounding off to 2 decimal places,
Answer is 0.06
Hope this helps. - M
5 obtuse no acute and no right