Answer:
27
Explanation:
Let x = ten's digit
Let y = units' digit
Given: the units of a two-digit numeral means
that our final answer will be a 2 digit number (xy)
Given: 5 more than the tens digit means
y is 5 more than x (y = x + 5)
Given: the number is three times the sum of its digits.
xy is 3 times x + y
A two digit positive integer can be written as 10x + y, where x is the tens digit and y is the ones digit
y = x + 5 and 10x + y = 3(x + y)
x - y = -5
7x - 2y = 0
Multiply the first equation by -2:
-2x + 2y = 10
7x - 2y = 0
Add the equations to get 5x = 10
So, x = 2 and y = x + 5 = 7
Reminder:
Let x = ten's digit
Let y = units' digit
The number is 27