What is the value of x when -3x + 7x = -12?
i just want to make sure my steps are in the right direction on this.

1-for what value of x is line a parallel to line b 2-for what value of x is line a parallel to line b

Liz is shipping a package to her friend.the maximum weight of a medium flat-rate box is 20 pounds,including the box which weighs 6 ounces.write and solve an inequality to describe the possible weight ,w, of the contents that liz will ship to her friend if she must use a medium flat-rate box.

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)