Question

What two numbers add to make twenty and have a difference of four?

smaller number = a0 and larger number = a1

Answer 1

8 and 12

Explanation:

I just use guess and check for these problems. Find something that works for the first and see if the same is true for the second. Someone else might know how to properly set it up, but I cant recall how to.

Answer 2

`a_0=8\,,\,a_1=12`

Explanation:

According to question, let smaller number be
`a_0` and larger number be
`a_1`.

Given that sum of two numbers is 20 and difference is 4, we get equations as

follows:

`a_0+a_1=20\\a_1-a_0=4`

From first equation , we get
`a_0=20-a_1`

On putting this in the second equation, we get

`a_1-\left ( 20-a_1 \right )=4\\a_1-20+a_1=4\\2a_1-20=4\\2a_1=20+4\\a_1=12`

On putting
`a_1=12` in equation
`a_0=20-a_1`, we get

`a_0=20-a_1=20-12=8`

So, two numbers whose sum is 20 and difference is 4 are 12 and 8