How do you solve the following system: #9x - 3y = -30, 4x + 2y = 0 #?

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Answer 1 · 2018-03-09T13:01:47

Arrange the equations. Get #x=-2# and #y=4#

Expand the first equation with 2 and the second equation with 3:

#18x - 6y = -60#
#12x + 6y = 0#

Sum these up:

#30 x = -60#

#x=-2#

Now you can compute the value of y (I use the second original equation to find the value of y):

#(4times-2) + 2y= 0#

#2y = 8#

#y=4#