Question 863273
A number is four less than four times another number (n). Therefore, the first number is 4n-4. If their sum is 21, meaning that {{{4n-4+n=21}}}
Combine Like Terms
{{{5n-4=21}}}
Add 4 to both sides
{{{5n=25}}}
Divide both sides by 5.
n=5. Because the second is 4n-4, it's 16
The numbers are 5 and 16.