Question

2a+5b+7,8a-7b+4,-5a-8b-4​

Answer 1

`Sum = 5a -10b+7`

Step-by-step explanation:

Given

`2a + 5b + 7`,
`8a-7b+4`,
`-5a-8b-4`

Required

Add (Missing from the question)

The summation of
`2a + 5b + 7`,
`8a-7b+4`,
`-5a-8b-4` is:

`Sum = 2a + 5b + 7 + 8a-7b+4-5a-8b-4`

Collect Like Terms

`Sum = 2a + 8a-5a+ 5b -7b-8b+ 7 +4-4`

`Sum = 5a -10b+7`