TrHaydSolet TrHaydSolet 02-07-2016 Mathematics contestada solve the system of equations using substitution. 3 multiplied by y equals negative the quantity 1 divided by 2 end of quantity multiplied by x plus 2. y equals negative x plus 9. a. (20, –4) b. (10, –1) c. (3, 6) d. (–1, 8)