Question

How many solutions does the system below have?

2x + 6y = 12
y =
= -x + 2
1 solution
2 solutions
no solutions
infinite solutions

Answer 1

Answer: 1 solution

An augmented matrix for the system is
[2,6,12;1,1,2] where we will call the first two columns A and the third b. A is linearly independent since it is row equivalent to the identity matrix, which tells us that for any b there will be a unique solution (x,y).