the sum of two numbers is 15 and the difference is 5 what are the two numbers

Answer 1

the sum of two numbers is 15 and the difference is 5 what are the two numbers.

This problem can be solved with a system of equations. We can write the following equations to represent the sum and difference of two unknown numbers.

x+y=15

x-y=5

The way to solve this is to add the equations together. When we do that, we end up with 2x=20.

Then divide both sides by 2 to solve for x. Once you have your x value, you can plug it into either of your original equations above to solve for y. This will give you your two numbers.

Answer 2

Hi Delilah,

Let's draw bar charts;

Number 1 [_____][__5__]

Number 2 [_____]

1 Unit = [_____]

As you can see, Number 1 is longer by 5.

Since total of both number is 15, let's remove the extra 5 from the chart

15-5 = 10.

What is left is;

Number 1 [_____]

Number 2 [_____]

And now the total is 10.

Therefore, 1 unit is 10÷2 = 5

Now, we can find out what the original 2 numbers were;

Number 1 is 5+5 = 10

Number 2 is 5

To illustrate this;

Number 1 [__5__][__5__]

Number 2 [__5__]

5+5+5 = 15, which proves that we are correct

Answer 3

This is a system of equations. You must write the equations first.

Start by choosing variables, let's say a & b.

The sum of two numbers is 15. Sum means addition. So the equation is:

a + b = 15

The difference is 5. Difference means subtraction. So the equation is:

a - b = 5

Now we will solve with elimination to eliminate the variable "b". We can add the 2 "a"s and (-b + b = 0) and then add the constants on the other side of the equal signs.

(a + b = 15)

+

(a - b = 5)

____________

2a = 20

Now we divide by 2 on both sides to isolate the "a".

2a = 20

_________ =

2

a = 10

To find "b" we can plug "a" into either equation

a + b = 15

10 + b = 15

Subtract 10 on both sides to find b

b = 5

a = 10

b = 5

Answer 4

Hello Delilah,

The two numbers are 10 and 5.

10+5 = 15 (sum)

10-5 = 5 (difference)