Question

How many solutions exist for the system, x + y = 1 and y = -x + 1?
no solution
one solution
infinitely many solutions

Answer 1

solving the system of two equations with two unknowns means finding the point where those two lines intersect....if we can find that point, than your answer is one solution, if the lines are parallel no solutions and if they lie on the same direction infinitely many solutions...so if you try to draw your two lines you'll get something that looks like this:

Answer 2

actually if you look more careful, you have two equations which are the same if you express y in the first one...so you have to find where these two lines intersect...they lie on the same direction, so they intersect in every possible point, so your answer is infinitely many solutions...

Answer 3

Thank you soooo much !!

Answer 4

you're welcome cutenerd :D