Question

Solve By Substitution.....
{ 1/3x - 2/3 y-1=0
{ x+y+7=0

Answer 1

in the 1st equation, u will get 1/3x=2/3y+1 or, x=2y+3
in the second equation, substitute x with 2y+3
then u will get y=-10/3
put the value of y in any equation, u will get the solution for x

Answer 2

{ 1/3x - 2/3 y-1=0 (1)
{ x+y+7=0 (2) ------> x=-y-7 subs this to eq 1
(1/3)x -( 2/3)y -1=0
(1/3)(-y-7) -( 2/3)y -1=0 mult by 3
(-y-7) - 2y -3=0
-3y-10=0
-3y=10
y=-10/3 ans sub this to eq (2)
x+y+7=0
x-(10/3)+7=0
x=-7 +10/3
x=-21/3 +10/3
x=-11/3 ans