Q1. Solve using graphical method

Maximize z = 100x + 150y

Subject to x + 3y <= 120

35x + 10y <= 780

x <= 20

x >= 0

y >= 0

And Q2 is solving using Simplex Method...now I don't get this one at all. :L

Maximize z = 80x1 + 70x2

Subject to 6x1 + 3x2 <= 96

x1 + x2 <= 18

2x1 + 6x2 <= 72

x1 >= 0

x2 >= 0

Btw the number (after x and y) the below x and y...I don't know what you call it...

Thanks. Any help will be highly appreciated.