For the following system, if you isolated x in the second equation to use the Substitution Method, what expression would you substitute into the first equation?

3x + y = 8
-x - 2y = -10

Question

For the following system, if you isolated x in the second equation to use the Substitution Method, what expression would you substitute into the first equation?

3x + y = 8
-x - 2y = -10

henrietepurina · Answer

-2y + 10

 2y + 10

 2y - 10

 -2y - 10

henrietepurina · Answer

@ParthKohli

sleepyhead314 · Answer

try to solve for x from
-x - 2y = -10

sleepyhead314 · Answer

to do that you can  add 2y to both sides
then divide both sides by a  -1

henrietepurina · Answer

3x + 2y = -8
x = -10
am I close?

sleepyhead314 · Answer

hmmm not quite
all they want is for you to isolate x
from the equation  of   -x - 2y = -10
so add 2y to both sides     +2y           +2y
so   -x = 2y - 10
then divide both sides by  -1

henrietepurina · Answer

is it B cuz x = 2y + 10

sleepyhead314 · Answer

ooooooo
so close so close ^_^
don't forget that multiplying/dividing by -1
would mean that  -(2y-10)    and distribute the negative

henrietepurina · Answer

-2y + 10?

sleepyhead314 · Answer

correct ^_^

henrietepurina · Answer

yay thanks :)

sleepyhead314 · Answer

you're welcome :)