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4 votes
What are two numbers that have a product of 15 but also a sum of 8

2 Answers

4 votes

Answer:

3 and 5

Hope this helps!!!

Explanation:

Begin by creating the two equations that are provided by the information in the question.

x + y = 8

and

x y = 15

Now you can solve logically because of the simplicity of the numbers, by listing the factors of 15 and determine which pair will add up to 8

1 and 15

3 and 5

And Then The Answer is 3 and 5

Or you can solve algebraically by substitution

x + y = 8 can be converted to

y = 8 − x

Now substitute the first equation into the second equation for the y variable.

x ( 8 − x ) = 15

Distribute

8 x −x 2 = 15

Set the equation equal to zero.

8 x − x 2 − 15 = 15 − 15

Rearrange to put the squared term first.

− x 2 + 8 x − 15=0

or the trinomial.

-1(x-5)(x-3) = 0#

Set both factors equal to zero.

x − 5 = 0

x = 5

x− 3 = 0

x = 3

5 and 3

User Cerber
by
5.3k points
3 votes

Answer:

3 and 5

Explanation:

3+5=8, and also

3x5=15

User MrBlue
by
5.3k points