Step-by-step explanation:
let us start with
Molly's equation
15x + 10 = 100
solving for x we have
15x=100-10
15x=90
x=90/15
x=6
Maddie's equation
15x - 10 = 100
solving for x we have
15x=100+10
15x=120
x=120/15
x=8
well, from the solution niether of them is correct