Solve the system of linear equations below. x − 3y = -3 x + 3y = 9 a. x = -12, y = 7 b. x = 3, y = 2 c. x = 6, y = 1 d. x = 6, y = 2

ANSWER

B. x=3,y=2

EXPLANATION

The given equations are

and

We add the two equations to eliminate y.

This implies that that:

Simplify:

Divide both sides by 2.

We put x=3 into any of the equations to find y.

Let us substitute x=3 into equation (1) to get:

Divide both sides by -3 to get;

The solution is therefore x=,y=2.

f(x) = x^3 -2x^2 -3x

x( x^2 -2x-3)

x( x^2 +x -3x -3)

x( x(x+1) -3(x+1))

x( x-3)( x+1)

so zeroes are 0, 3,-1

its (2) option