In Euclidean plane geometry two infinitely long straight lines intersect at only one point
Not necessarily, as two lines can exist in one plane, but they don't always touch each other. An example would be parallel lines, where the lines are parallel to each other. Lines are also not necessarily straight all the time as it can be curvy too, wherein that a straight line or another curvy line that "does" touch the first curvy line could possibly intersect at more than one point.
Correct. Two lines never meet in more than one point.
They can only intersect at the circumcentre, which is a point outside the triangle, beyond the side opposite the obtuse angle.
Perpendicular lines intersect each other at right angles which are 90 degrees Parallel lines never intersect each other and remain the equal distance apart. Intersecting lines form vertical opposite equal angles
wrong!
In Euclidean plane geometry two infinitely long straight lines intersect at only one point
FALSE!!
no the definition is two lines intersecting once
it has 4 vertices, a vertice is a point were two lines intersect
Yes. Any two distinct lines of longitude, for example, meet at two points - the poles. On a plane, though, two points define a unique line. So if two lines intersect at more than one point they must be coincident.
If it is a linear system, then it could have either 1 solution, no solutions, or infinite solutions. To understand this, think of two lines (consider a plane which is just 2 dimensional - this represents 2 variables and 2 equations, but the idea can be extended to more dimensions).If the 2 lines intersect at a point, then that point represents a solution. If the lines are parallel, then they never intersect, and there is no solution. If the equations are such that they are just different ways of describing the same line, then they intersect at every point, so there are infinite solutions. If you have more than 2 lines then maybe some of them will intersect, but this is not a solution for the whole system. If all lines intersect at a single point, then that is the single solution for the whole system.If you have equations that describe something other than a straight line, then it's possible that they may intersect in more than one point.
No. A linear equation represents a straight line and the solution to a set of linear equations is where the lines intersect; two straight lines can only intersect at most at a single point - two straight lines may be parallel in which case they will not intersect and there will be no solution. With more than two linear equations, it may be that they do not all intersect at the same point, in which case there is no solution that satisfies all the equations together, but different solutions may exist for different subsets of the lines.
Graphically, it is the point of intersection where the lines (in a linear system) intersect. If you have 2 equations and two unknowns, then you have a 2 lines in a plane. The (x,y) coordinates of the point where the 2 lines intersect represent the values which satisfies both equations. If there are 3 equations and 3 unknowns, then you have lines in 3 dimensional space. If all 3 lines intersect at a point then there is a solution to the system. With more than 3 variables, it is difficult to visualize more dimensions, though.
No because the 2 straight lines can only intersect one another at one particular point
no they can't
Yes.