If 2x + 3y = 17 and 3x + 4y = 24, then what is 5x +7y? Algebra Systems of Equations and Inequalities Systems Using Substitution 1 Answer sankarankalyanam May 9, 2018 #color(indigo)(5x + 7y = (5 * 4) + (7 * 3) = 41# Explanation: #2x + 3y = 17, " Eqn (1)"# #6x + 9y = 51, color(red)(" Eqn (3) = 3 * Eqn (1)"# #3x + 4y = 24, " Eqn (2)"# #6x + 8y = 48, color(red)(" Eqn (4) = 2 * Eqn (2)"# #6x - 6x + 9y - 8y = 51 - 48, color(purple)(" Eqn (3) - Eqn (4)"# #y = 3# Substituting value of y in eqn 91), #2x + 9 = 17# #2x = 8, x = 4# #color(indigo)(5x + 7y = (5 * 4) + (7 * 3) = 41# 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 3193 views around the world You can reuse this answer Creative Commons License