The first number is 95 less than the second number. the sum of the two nos.is 135. what r d 2 nos?

f = s - 95 "the first number is 95 less than the second number."
f + s = 135 "the sum of the two numbers is 135."

You have two lines. Where they cross, the values of x and y satisfy both equations simultaneously, so it is called a simultaneous system. There are two ways to find that point. Substitution is when you solve one equation for one variable and substitute that into the other equation.

Elimination is when you add the equations in a way to eliminate one variable. Otherwise the process is the same.

f + s = 135
f = s - 95
------------- SUBTRACT
s = -s + 230

2s = 230

s = 115

f = 20