These questions need to be solved using Cramer's Rule, If you could please show the work as well, if that's possible, I'd appreciate it!

(a) x=2, y=-1

(b)  x=2, y=2

(c)

(d) x=-2, y=-7

Step-by-step explanation:

Cramer's Rule

It's a predetermined sequence of steps to solve a system of equations. It's a preferred technique to be implemented in automatic digital solutions because it's easy to structure and generalize.

It uses the concept of determinants, as explained below. Suppose we have a 2x2 system of equations like:

We call the determinant of the system

We also define:

And

The solution for x and y is

(a) The system to solve is

Calculating:

The solution is x=2, y=-1

(b) The system to solve is

Calculating:

The solution is x=2, y=2

(c) The system to solve is

Calculating:

The solution is

(d) The system to solve is

Calculating:

The solution is x=-2, y=-7

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step-by-step explanation: