How do you solve the system of equations #-7x + 6y = - 29# and #- x - 6y = - 11#?

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Answer 1 · 2016-12-04T15:27:32

#x = 5# and #y = 1#

Step 1) Solve the second equation for #x#:

#-1*(-x - 6y) = -1 * -11#

#x + 6y = 11#

#x + 6y - 6y = 11 - 6y#

#x = 11 - 6y#

Step 2) Substitute #11 - 6y# for #x# in the first equation and solve for #y#:

#-7(11 - 6y) + 6y = -29#

#-77 + 42y + 6y = -29#

#-77 + 48y = -29#

#-77 + 77 + 48y = -29 + 77#

#48y = 48#

#(48y)/48 = 48/48#

#y = 1#

Step 3) Substitute #1# for #y# in the solution to the second equation in Step 1) and calculate #x#:

#x = 11 - 6*1#

#x = 11 - 6#

#x = 5#