SOLUTION: using the two equations below solve for x and y using three different methods, substitution, addition, and graphing:
x-y=12
2x+y=3
Algebra ->
Expressions-with-variables
-> SOLUTION: using the two equations below solve for x and y using three different methods, substitution, addition, and graphing:
x-y=12
2x+y=3
Log On
Question 110279: using the two equations below solve for x and y using three different methods, substitution, addition, and graphing:
x-y=12
2x+y=3 Answer by edjones(8007) (Show Source):
You can put this solution on YOUR website! A) x-y=12
B) 2x+y=3
.
substitution:
A) x-y+y=12+y
x=12+y
2(12+y)+y=3 substitute 12+y for x.
24+2y+y=3
3y+24-24=3-24
3y=-21
y=-7
A) x-y=12
x+7=12
x+7-7=12-7
x=5
.
addition:
B) 2x+y=3
A) x-y=12
-----------add
==>3x=15
x=5
A) x-y=12
5-y=12
5-5-y=12-5
-y=7
-y*-1=7*-1
y=-7
.
Ed
