lanzy1 lanzy1 22-02-2020 Mathematics contestada simplify15a-6a+9a+b=5m+7n+8m-3n=9x+7y-3x+2y=14L-6L+5m+18m-9m=8x+7y-6x-3y=5x+8y+9x-3y-2y=5a+3b+4a=