Answer:
<em>(a) x=2, y=-1</em>
<em>(b) x=2, y=2</em>
<em>(c)</em>
<em>(d) x=-2, y=-7</em>
Step-by-step explanation:
<u>Cramer's Rule</u>
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