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How do you solve y= 4x + 45 and x= 4y?

1 Answer

Oct 4, 2015

#x=-12#, #y=-3#

Explanation:

Knowing that #x=4y#, you can write the first equation as

#y=4(4y)+45 -> y=16y+45 -> -15y=45#, isolating the #y#-terms by bringing them all to the left. Now, solving by #y#, we have #y=-3#.

Since #x# was #4y#, we know that #x=4*(-3)#, and thus #x=-12# and the system is solved.

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