If the sum of two numbers is 48, we can call our numbers x and 48 - x.
Let's call our first number x and our second number 48 - x.
Now read through the rest of the problem.
The second, 48 - x, is, equals, 3 more than 4 times the first, 4x + 3.
So we have the equation 48 - x = 4x + 3.
Solving from here, we subtract 4x from both sides and we have 48 - 5x = 3.
Now subtract 48 from both sides and we have -45 = -5x.
Finally, divide both sides by -5 and remember that
a negative divided by a negative always equals a positive.
So we have 9 = x.
So our first number is x and our second is 48 - x or 48 - 9 which is 39.
