You need two equations to use the addition method.
Chat with our AI personalities
(4, 3)
The answer is 7.
5b = 21 + 4b 5b - 4b = 21 + 4b - 4b b = 21
4a - 5b = 74a +5b = 17From the first equation:4a = 7 + 5bsubstitute this value in the second equation:7 + 5b + 5b = 177 + 10b = 1710b = 10b = 1Now,solve for a :4a - 5(1) = 74a = 7 + 54a = 12a = 3
b= -162