1.

Find the value of x that optimize the following function:

y=f(x)=-3x² +12x +3

2.

Solve the equations below for x and y

6x+3y=60

6x-2y=80

3.

Given the following functions: (1) y=4+2x

(2) y=10-2x

Solve the above equations for the equilibrium value of X and Y.