# SOLUTION: 2x + y = 15 x + 2y = 18

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 Question 68532This question is from textbook Algebra 1 for Chirstian Schools : 2x + y = 15 x + 2y = 18This question is from textbook Algebra 1 for Chirstian Schools Answer by rmromero(383)   (Show Source): You can put this solution on YOUR website!There are several Steps to Graph these equations. One way is by Using the Slope - Intercept Form. 1. Rewrite the equation to y = mx + b, where m = the slope and b = y-intercept. From --->2x + y = 15 y = -2x + 15 , m = -2 and b = 15 To graph the b will help you plot the first point. Since b = 15, you point is located (0, 15).The m is the . Since m = -2, we can rewrite it . From point (0, 15), we will move 2 units down because 2 is negative and 1 unit right because 1 is positive. 2. x + 2y = 18 Rewrite the equation to y = mx + b. x + 2y = 18 2y = -x + 18 , m = b = 9 , From point (0, 9), we will move 1 unit down and 2 units right. If you want to combine the two equation, the graph looks like this. Green line is the graph of x + 2y = 18 and the red line shows the graph of 2x + y = 15 If you want to find the intersection of the graph: Here are the Steps using Substition method 1. In either equation, solve for one variable in terms of the other. x + 2y = 18 x = -2y +18 2. Substitute -2y + 18 for x in the other equation 2x + y = 15. Solve y. 2x + y = 15 2(-2y+18) + y = 15 -4y + 36 + y = 15 -3y = -21 y = 7 3. Substitute the result from step 2 in either equation. Solve for the other variable. 2x + y = 15 , y = 7 2x + 7 = 15 2x = 8 x = 4 4. Check the solution in both original equations. 2x + y = 15 , x = 4 and y = 7 2(4) + 7 = 15 8 + 7 = 15 15 = 15 ----------->> True x + 2y = 18, x = 4 and y = 7 4 + 2(7) = 18 4 + 14 = 18 18 = 18 ---------->> True The Solution of the equation is x = 4 and y = 7, Meaning the graph will meet when x = 4 and y = 7