Answer:
Yes. No graph paper.
Step-by-step explanation:
Let's say the 3 points are A, B, C.
If A, B and C lie on one line then 

Hence, they lie on one line.
You don't need to use a graph paper to prove it.
The country population would be 827 million in about 20 years.
This can be found by replacing "t" with 20 and solving. The solution would be about 8273.28 million. Thus meaning in about 20 years, the population would be 827 million.
(x + 2)(5x^2 + x - 4) =
x(5x^2 + x - 4) + 2(5x^2 + x - 4) =
5x^3 + x^2 - 4x + 10x^2 + 2x - 8 =
5x^3 + 11x^2 - 2x - 8 <===