How can we solve the simultaneous equations #3x-6y=-9# and #3x-4y=-13#?

1 Answer
Feb 2, 2017

Answer:

#x=-7# and #y=-2#

Explanation:

The equations are

#3x-6y=-9# ................................(1)

#3x-4y=-13# ................................(2)

As we have #3x# in both the equations, system of equations can be solved by eliminating this term, which can be done by subtracting equation (2) from (1). Doing this, we get

#-6y-(-4y)=-9-(-13)#

or #-6y+4y=-9+13#

or #-2y=4# and #y=-4/2=-2#

Now putting this in (1), we get

#3x-6xx(-2)=-9#

or #3x+12=-9#

or #3x=-9-12=-21#

i.e. #x=-21/3=-7#

Hence, #x=-7# and #y=-2#