Which equation shows the substitution method being used to solve the system of linear equations?

x + y = 6
x = y + 5

A.
x = (x – 6) + 5

B.
(y + 5) + y = 6

C.
x + (y + 5) = 6

D.
x + y = y + 5

Question

Which equation shows the substitution method being used to solve the system of linear equations?
 
x + y = 6
x = y + 5
 
 
 A.
x = (x – 6) + 5
 
 B.
(y + 5) + y = 6
 
 C.
x + (y + 5) = 6
 
 D.
x + y = y + 5

alexandervonhumboldt2 · Answer

substitute the value of x into the first equation:
x + y = 6
x = y + 5

=>  (y+5)+y=6   =>  2y=1     =>  y=1/2

x+1/2=6
x=5.5


thus  y=0.5 and x=5.5

ellaella02 · Answer

Thank you so much (:

ellaella02 · Answer

But none of them are right?... @AlexandervonHumboldt2

alexandervonhumboldt2 · Answer

no

you need to susbtitute the value of x into first equation.
x=y+5.

substitue this instead of x: (y+5)+y=6