Answer:
Different ways to solve a system of linear equations:
isolate one variable in one equation and replace it in the other equation
multiply/divide one equation by a constant and then add/subtract it to the other one, so that only one variable remains
graph the equation and look at the intersection point
If you graph the system:
there is only one solution if the lines intersects at only one point
there is no solution if the lines don't intersect each other (they are parallel)
there are infinitely many solutions if the lines overlap each other (they are the same equation multiplied by some constant)
Step-by-step explanation:
1st system
y = -x – 7
y = 4/3 x – 7
solution: x= 0, y = 7
2nd system
y = -3x – 5
y = x + 3
solution: x = -2, y = 1
3rd system
y = -2x + 5
y = 1/3 x – 2
solution: x = 3, y = -1
4th system
3x + 2y = 2
x + 2y = -2
solution: x = 2, y = -2
5th system
x + 3y = -9
2x – y = -4
solution: x = -3, y = -2
6th system
x – 2y = 2
-x + 4y = -8
solution: x = -4, y = -3
7th system
5x + y = -2
x + y = 2
solution: x = -1, y = -3
