How do you solve the system of equations #-7x - 8y = - 10# and # 5x - 3y = 20# using augmented matrices?

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Answer 1 · 2017-10-24T15:17:05

The answer is #((x),(y))=((1330/427),(-90/61))#

Let's perform the Gauss Jordan elimination on the augmented matrix

#((-7,-8,|,-10),(5,-3,|,20))#

Perform the operations on the rows

#R1larr(R1)/(-7)#

#((1,8/7,|,10/7),(5,-3,|,20))#

#R2larr(R2)/(5)#

#((1,8/7,|,10/7),(1,-3/5,|,4))#

#R2larr(R2-R1)#

#((1,8/7,|,10/7),(0,-61/35,|,18/7))#

#R2larr(R2)*(-35/61)#

#((1,8/7,|,10/7),(0,1,|,-90/61))#

#R2larr(R1)-(8/7R2)#

#((1,0,|,1330/427),(0,1,|,-90/61))#