What are the 2 numbers if the sum is 70 and they differ by 11? Algebra Systems of Equations and Inequalities Systems Using Substitution 1 Answer seph Nov 1, 2014 x + y = 70 x - y = 11 Add the two equations (x + y) + (x - y) = 70 + 11 2x = 81 x = 40.5 x + y = 70 40.5 + y = 70 y = 70 - 40.5 y = 29.5 Your two numbers are 40.5 and 29.5 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? 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? How do you solve x-5y=15 and 4x-3y=26 using substitution? See all questions in Systems Using Substitution Impact of this question 10759 views around the world You can reuse this answer Creative Commons License