Question 314472
Since we want to maximize the number of 3 point baskets, the other baskets must be 1 pointers.

Let x be the number of 1 point baskets. 
Then the number of 3 point baskets is {{{50-x}}}

Then 1 point baskets plus the 3 point baskets total 80 points. So
{{{x + 3(50-x) = 80}}}
{{{x + 150 -3x = 80}}}
{{{-2x = -70}}}
{{{x = 35}}}
The number of 1 point baskets is 35. 
The number of 3 pointers is {{{50-x = 50-35 = 15}}}
Check your answer
Does 15*3 + 35 = 80?