How do solve the following linear system?: # 3 x-2y=4 , 3y = 15 -x #?

1 Answer
Jan 12, 2016

The solution for the system of equation is
#color(blue)(x=42/11 ,y=41/11#

Explanation:

#color(blue)(3x) -2y=4# .....equation #(1)#

#x + 3y=15#, multiplying by #3#
#color(blue)(3x) + 9y=45# .....equation #(2)#

Solving by elimination

Subtracting equation #2# from #1#

#cancelcolor(blue)(3x) -2y=4#
#-cancelcolor(blue)(3x) - 9y=-45#

#-11y = -41#

#color(blue)(y = 41/11#

Finding #x# from equation #2#

#x + 3y=15#

#x =15 - 3y#

#x =15 - 3 xx 41/11#

#x =15 - 123/11#

#x =165/11 - 123/11#

#color(blue)(x =42/11#