How do you solve the following system?: #5x + 2y =1 ,3x-7y=-12#

Question

1784 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-03-06T16:21:01

#x=-17/41#

#y= 63/41#

#5 * x + 2 * y = 1#

#3 * x - 7 * y=-12#

Multiply the first equation by #3.5#

#17.5 * x + 7 * y = 3.5#

#3 * x - 7 * y=-12#

Add the two equations to get

#20.5 * x + cancel(7y) - cancel(7y) = -8.5#

#x = -8.5/20.5 = -17/41#

This means that you have

#3 * (-17/41) - 7y = -12#

#y = (12 - 3 * 17/41)/7 = 63/41#