Question

Write a system of two equations using x and y in each for the following.

The sum of two numbers is 170 and their difference is 26. Find the two numbers.

Answer 1

Given:
y+x=170
y-x=26
so solve for one variable.
y=170-x
and plug it into the second equation

y-x=170
(170-x)-x=26
170-2x=26
196=2x (put all like terms on one side. remember what you do to one side you have to do to the other side. I just added +2x on both sides and minus 26 on both sides)
x=98 (now divide)
and now you solve for y
if x=98 then...
y+x=170
y+98=170
y=72