SOLUTION: Determine two solutions of the equations and use the points to determine the slope of the line. Problem 39: x+2y=0

Algebra ->  Linear-equations -> SOLUTION: Determine two solutions of the equations and use the points to determine the slope of the line. Problem 39: x+2y=0      Log On


   

Question 132325This question is from textbook Elementary Algebra
: Determine two solutions of the equations and use the points to determine the slope of the line.
Problem 39: x+2y=0 This question is from textbook Elementary Algebra

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x%2B2y=0 Start with the given equation


2y=0-x Subtract +x from both sides


2y=-x Simplify


y=%28-1%2F2%29x Divide both sides by 2 to isolate y




In order to graph this equation, we only need two points to create a straight line




--------------------------------Let's find the first point--------------------------------

y=-%281%2F2%29x Start with the given equation




y=-%281%2F2%29%280%29 Plug in x=0 (you can start with any number, but zero is the easiest number to work with since anything multiplied by zero is zero)




y=0%2B0 Multiply -1%2F2 and 0 to get 0




y=0 Add



So when x=0, we have the value y=0. This means we have the first point




--------------------------------Let's find the second point--------------------------------

y=-%281%2F2%29x Start with the given equation




y=-%281%2F2%29%282%29 Plug in x=2




y=-2%2F2%2B0 Multiply -1%2F2 and 2 to get -2%2F2




y=-1%2B0 Reduce -2%2F2 to get -1




y=-1 Add



So when x=2, we have the value y=-1. This means we have the second point




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So we have the two points: and


Now plot these two points on a coordinate system





Now draw a straight line through the two points. This line is the graph of y=-%281%2F2%29x

Graph of y=-%281%2F2%29x through the two points and