How do you solve the system 2y+6=x2y+6=x and y-3x=-13y3x=13 using substitution?

1 Answer
May 27, 2015

2y+6=x2y+6=x ...............equation (1)(1)

y-3x=-13y3x=13
y = -13 +3xy=13+3x........equation (2)(2)

substituting equation (2)(2) in equation (1)(1)
2y+6=x2y+6=x
2(-13 +3x) +6 = x2(13+3x)+6=x
- 26 +6x +6 = x26+6x+6=x
6x -x = 206xx=20
x = 20/5 = 4x=205=4

substituting this value of xx in equation 2
y = -13 +3xy=13+3x
y = -13 +3.(4)y=13+3.(4)
y = -13 +12 = -1y=13+12=1

the solutions for the system of equations are
color(purple)(x=4 and y =-1x=4andy=1