How do you solve the #x#-value in the system of equations #5x+4y=8# and #2x-3y=17#?

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Answer 1 · 2016-12-21T20:11:18

#x=4, y=-3#

We solve the linear equations simultaneously. With the first equation,

#5x+4y=8#, we develop an expression for #y#:

#y=(8-5x)/4#

And then we substitute this expression into the 2nd equation:

#2x-3y=17#

#2x-3xx(8-5x)/4=17#

#2x-24/4+15/4x=17#

#23/4x-24/4=17#

#23x=23xx4#, thus #x=4#.

And substitute back to get #y=-3#.

These values solve the 2 equations simultaneously.