How do you solve the following system?: #7x +y =-2 , -7x +y = -9# Algebra Systems of Equations and Inequalities Systems Using Substitution 1 Answer SagarStudy Jan 22, 2016 #7x+y=-2....................(i)# #-7x+y=-9........................(ii)# Add (i) and (ii) #implies 2y=-11# #implies y=-11/2# Put #y=-11/2# in #(i)# #implies 7x-11/2=-2# multiply both sides by #2# #implies14x-11=-4# #implies 14x=7# #implies x=1/2# Answer link Related questions How do you solve systems of equations using the substitution method? How do you check your solutions to a systems of equations using the substitution method? When is the substitution method easier to use? How do you know if a solution is "no solution" or "infinite" when using the substitution method? How do you solve #y=-6x-3# and #y=3# using the substitution method? How do you solve #12y-3x=-1# and #x-4y=1# using the substitution method? Which method do you use to solve the system of equations #y=1/4x-14# and #y=19/8x+7#? What are the 2 numbers if the sum is 70 and they differ by 11? How do you solve #x+y=5# and #3x+y=15# using the substitution method? What is the point of intersection of the lines #x+2y=4# and #-x-3y=-7#? See all questions in Systems Using Substitution Impact of this question 1131 views around the world You can reuse this answer Creative Commons License