Math
posted by Nikki .
Can someone please please help me understand how to go about solving this? (not really answering it, but actually explaining itpretty please?)
"The zipper and the safety pin were invented in the 14th century. The safety pin was invented 44 years before the zipper. The sum of the years in which they were invented is 3742. In what year was the zipper invented?"

x+y=3742
x=y44
y44+y=3742
2y44=3742
2y=3786
y=1893
Now plug that back into either of the first two equations to solve for x.