SOLUTION: Please solve: x+3y=9 x=3 What happens when there is no y also problem #12, what happens when there is no x

Algebra ->  Linear-equations -> SOLUTION: Please solve: x+3y=9 x=3 What happens when there is no y also problem #12, what happens when there is no x      Log On


   

Question 194909This question is from textbook Integrated Algebra 1
: Please solve:
x+3y=9
x=3
What happens when there is no y
also problem #12, what happens when there is no x This question is from textbook Integrated Algebra 1

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Remember that a linear equation is a rule that describes a set of ordered pairs, the coordinates of which make the equation a true statement. So, if you don't have a y variable, such as in x = 3, then you are describing the set of ordered pairs where 3 is always the x coordinate, and the y coordinate can be anything -- in other words, a vertical line that intersects the x-axis at (3,0).

If there is no x variable, then you have a horizontal line.

For the system:





You are given the value of x, so just substitute it into the first equation:



And solve for y.


John