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

x – y = 7
x = y + 3

A.
(y + 3) – y = 7

B.
x – (y + 3) = 7

C.
x = (7 – x) + 3

D.
x – y = y + 3

Question

Which equation shows the substitution method being used to solve the system of linear equations? 
 
x – y = 7 
x = y + 3
 
 A.
(y + 3) – y = 7
 
 B.
x – (y + 3) = 7
 
 C.
x = (7 – x) + 3
 
 D.
x – y = y + 3

anonymous · Answer

i am pretty sure it is a i am not sure i will medal and fan!

anonymous · Answer

plz anybody help! i really want to learn this

danjs · Answer

substitution is solving one of the equations for a variable, then subbing that into th enext equation , to reduce it to a single variable to solve for

anonymous · Answer

what you just said seems like my answer is correct, because what you said that answer explains

danjs · Answer

yeah , they already had one solved for you x=y+3    ,   put y+3 into the first equation for the x

anonymous · Answer

ok

anonymous · Answer

thx! a is correct i am writing down what you said lol

danjs · Answer

that goes down to 3 = 7, false,   no solutions for this system

anonymous · Answer

wait so a is wrong? ugh time to re do

anonymous · Answer

ok i have done so and have discovered that it is either b or c, i am leaning to c though

danjs · Answer

A is right

simplifying that though you get 3=7, false

anonymous · Answer

oh ok thx

danjs · Answer

so A shows the substitution method,   that is all they want,  but further,  the system has no solutions