1) Question 3
The system
y = 3.5x - 3.5
y = -3.5x +3.5
has one solution.
To find it, you can add the two equations:
2y = 0 => y =0
Now replace that value in any of the two original equations.
Doing it with the first of the equations:
=> 3.5x - 3.5 = 0=> 3.5x = 3.5 = x = 3.5 / 3.5 = 1
Solution (1,0)
Answer: one solution.
2) Question 4
The graph of a system of equations will intersect at more than 1 point.
Some times:
For example:
y = x + 2
2y = 2x + 4
Intersects in infinite points.
y = x + 2
y = x + 3
will not intersect
y = 2x
y = x+1
will intersect at one point.
And a system with a quadratic equation and a linear equation may drive to intersection in two points.