Solving a word problem with 2 unknown linear

Question

A washer and dryer cost $903 combined The washer costs $47 less than the washer What is the costs of the dryer

Answer 1

W+D=903

W=D-47

substitute 2nd equation's value of W into the 1st equation

(D-47)+D =903

2D=903+47=950

2D=950

D=950/2=475

Dryer costs $475

Washer costs 475-47= $428