Solve By Graphing

Question

Solve by graphing. (If there is no solution, enter NO SOLUTION. Use the parameters x and y as necessary.)
x − y = −2
x + 2y = 22

(x,y) format

Answer 1

x - y = -2 => y = x + 2

 

Substitute this into the second equation:

 

x + 2y = 22

x + 2(x + 2) = 22

x + 2x +4 = 22

3x = 18

x = 6

 

Then y = x + 2 = 8

 

(x,y) = (6, 8)

Answer 2

Hi Jane

 

x − y = −2    (1)

 

x + 2y = 22   (2)

 

From equation (1) you get x:   x = -2 + y (1a)

 

Substitute equation (1a) into equation (2) above:   x + 2y  = 22

 

                                                                        (-2 + y) + 2y = 22

                                                                         -2  + y + 2y = 22

                                                                               3y  = 22 + 2  

 

                                                                                 y = 24/3        y = 8

 

Using this y value in equation (1):    
x − y = −2 (1)

 

x - 8 = -2      x = -2 + 8  = 6       x = 6