SOLUTION: solve using the addition method. #1 x-y=6 3x+y=-2 #2 3x-4y=7 x+4y=5 #3 4x+5y=5 6x+7y=7 #4 2x+3y=13 3x-5y=10 #5 x+y=4 2x+3y=7

Algebra ->  Systems-of-equations -> SOLUTION: solve using the addition method. #1 x-y=6 3x+y=-2 #2 3x-4y=7 x+4y=5 #3 4x+5y=5 6x+7y=7 #4 2x+3y=13 3x-5y=10 #5 x+y=4 2x+3y=7       Log On


   



Question 5000: solve using the addition method.
#1
x-y=6
3x+y=-2


#2
3x-4y=7
x+4y=5


#3
4x+5y=5
6x+7y=7


#4
2x+3y=13
3x-5y=10


#5
x+y=4
2x+3y=7


#6
8x-10y=2
7x-5y=13

Answer by NinangS(5) About Me  (Show Source):
You can put this solution on YOUR website!
to add you need to eliminate one of your variables
1)
x-y=6
+3x+y=-2
___________
4x=4 divide bothe sides by 4
x=1
3(1)+y=-2
3+y=-2 subtract 3 from both sides
y=-5
2)
3x-4y=7
+ x+4y=5
___________
4x=12
x=3
3+4y=5
4y=2
y=.5
3)
4x+5y=5 = [3]4x+5y=5 = 12x+15y=15
+ 6x+7y=7 = [-2]6x+7y=7 =-12x-14y=-14
______________________________________
y=1
4x+5(1)=5
4x=0
x=0
4)
2x+3y=13 = [5]2x+3y=13 = 10x+15y=65
+3x-5y=10 =[3]3x-5y=10 = 9x-15y=30
_____________________________________
x=95
3(95)-5y=10 = 285-5y=10
-5y=-275
y=55
5)
x+y=4 = [-2]x+y=4 = -2x-2y=-8
+2x+3y=7 = 2x+3y=7 = + 2x+3y=7
_______________________________
y=-1
x+(-1)=4
x=5
6)
8x-10y=2 = 8x-10y=2
+7x-5y=13 = [-2]7x-5y=13 = + -14x+10y=-26
________________________________________
-6x=-24
x=4
32-10y=2
-10y=-30
y=3