If you were to use the substitution method to solve the following system, choose the new equation after the expression equivalent to x from the first equation is substituted into the second equation.
x + 2y = 4
x – 5y = 11

Question

If you were to use the substitution method to solve the following system, choose the new equation after the expression equivalent to x from the first equation is substituted into the second equation.
x + 2y = 4
x – 5y = 11

johnweldon1993 · Answer

Well when you solve that first equation for 'x' you get

x = 4 - 2y

So after you substitute that into the second equation for 'x' you get

4 - 2y - 5y = 11

anonymous · Answer

x – 5(2y + 4) = 11

 x – 5(–2y + 4) = 11

 (2y + 4) – 5y = 11

 (–2y + 4) – 5y = 11

anonymous · Answer

those are my multiple choice options A,B,C,D

anonymous · Answer

@johnweldon1993

anonymous · Answer

@primeralph helpppp :)

johnweldon1993 · Answer

Oh...just a rearranging of what I put...

x = -2y + 4 is the same thing..so

-2y + 4 - 5y = 11

johnweldon1993 · Answer

Wait @primeralph is it B? Doesnt the question tell us to isolate 'x' in the first equation?

johnweldon1993 · Answer

No no no...it's D like I said lol

primeralph · Answer

Oh yeah.

primeralph · Answer

Need to go eat something.

anonymous · Answer

Okay thankyou guys :)

johnweldon1993 · Answer

lol go refuel Primeralph! haha...and anytime @juliaann :)