One number is seven more than three times another number. If the sum of the numbers is 15, find the numbers.

Mathematics

1 answer:

dimulka [17.4K]3 years ago

4 0

Answer:

2 and 13

Step-by-step explanation:

We can use systems of equations here to find both the numbers. Let's assume one of the numbers is $x$ and the other is $y$ .

We know that these numbers add up to 15, so $x + y = 15$ .

We also know that one of these numbers is 7 more than 3 times the other, so $x = 3y + 7$ .

We can now substitute the equation $x = 3y + 7$ into $x + y = 15$ .

$(3y + 7) + y = 15$

Combine like terms:

$4y + 7 = 15$

Subtract 7 from both sides:

$4y = 8$

Divide both sides by 4:

$y = 2$ .

Now that we know the value of $y$ , we can substitute it inside an equation to find $x$ . Let's substitute it inside $x + y = 15$ .

$x + 2 = 15\\\\x = 15-2\\\\x = 13$

So the two numbers are 2 and 13.

Hope this helped!

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