ok do you know what a system of equations is
A system of equations is a collection of two or more equations with a same set of unknowns. In solving a system of equations, we try to find values for each of the unknowns that will satisfy every equation in the system. The equations in the system can be linear or non-linear.
Now that you know this would you rather solve it by elimination or substitution
I solve the second equation with respect to e, and I find: \[\Large e = d - 5\]
Now substitue that into the other equation
idk how to do this
we have: 2d-5=15 then 2d=20 and d=20/2=...?