Need help with homework

2x + y = -1   and   -x + y = -7

 

y = x - 7          from second equation, isolate y

2x + x - 7 = -1      plugin second equation into first

3x - 7 = -1          add the x together

3x = 6            add 7 to the other side to isolate x

x = 3          divide 6 by 3 to isolate x

y = 3 - 7        plugin x for the 3rd isolate y equation

y = -4           add

(3, -4) 

 

-lekrj :) did you understand? hope you did

y=x-2 and 2x+y=4

 

2x+ (x-2)=4     plug in the x-2 into y

3x - 2 = 4        add x with 2x

3x = 6              add 2 to the other side to isolate x

x= 3                 divide 6 by 3 to isolate x

y = 3 - 2           plug in 3 for x

y = 1               3 minus 2 is 1

(3, 1)

 

-lekrj