How do you solve the system using the elimination method for 3x - 4y = 9 and 2x + 3y = 7?

Question

6431 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-06-02T08:20:17

See below

We have two linear equations (to be solved by elimination method)

#3x-4y=9#
#2x+3y=7#

Multiply first eq. by #-2# and second by #3#

#-6x+8y=-18#
#6x+9y=21#

Now we can add both equations and eliminate the unknown x

#17y=3#

#y=3/17#

#x# can be found in first equation (for example)

#3x-4·3/17=9#
#3x=9+4·3/17#
#x=55/17#

Solution is the pair of values #(3/17,55/17)#