A number is 7 more than another number. The sum of the numbers is 15. Find the numbers.

Answer 1

Hello Mackenzie,

y = x + 7 <-----"A number is 7 more than 'another' number."

y + x = 15 <-----"The sum of the 'numbers' is 15."

Since we know what y is, why not use substitution? Let's solve for x, first, okay?

x + 7 + x = 15

2x + 7 = 15

2x = 8

x = 4

Now, let's substitute x's value of 4 and substitute 4 for x.

y = x + 7

y = 4 + 7

y = 11

Now, let's check our work, okay? Do the two numbers meet the requirements as outlined in the problem? Yes. The numbers check out and the solution is valid. I hope this assists and wish you a good week. If you have any feedback, or need further clarity, or have more questions regarding the solution I provided please feel free to click the "Add Comment" prompt. If you have a need for one-on-one tutor, please feel free to click on my profile and send me a request through the Wyzant system. Best!