How do you solve this system of equations: #-x + 2y = 10 and 3x + 4y = - 10#?

1 Answer
Dec 10, 2017

the solutions are #x=-6,y=2#

Explanation:

given system of equations
#-x+2y=10->(1)#
#3x+4y=-10->(2)#
multiplying# (1)# by #3# we get
#-3x+6y=30->(3)#
#(3)+(4)#
#-3x+6y-30+3x+4y+10=0rArr10y-20=0#
#rArr10y=20rArry=2#
put #y=2 # in #(3)# we get
#-3x+12=30rArr-3x=18rArrx=-6#
#:.x=-6,y=2#