SOLUTION: a number is four less than four times another number. if their sum is 21 find the numbers

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Question 863273: a number is four less than four times another number. if their sum is 21 find the numbers
Answer by ben720(159) About Me  (Show Source):
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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%2Bn=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.