Question

How do you solve `4z - 7+ 4( z + 1) = - ( 5z - 5)`?

Answer 1

`z=8/5`

Explanation:

`color(blue)("Note that:")`
For `4(z+1)` Multiply everything inside the bracket by +4
`=>+4(z+1)= 4z+4`

For `-(5z-5)` multiply everything inside the bracket by -1
`=>-(5z-5)=-5z+5`
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`color(blue)("Putting it all together")`

`4z-7+4z+4=-5z+5`

But `4z-4z=0" and "4-7=-3`

`0-3=-5z+5`

To make the `-5z` positive multiply both sides by -1

`+3=+5z-5`

Add 5 to both sides

`3+5=5z+0`

Divide both sides by 5

`(3+5)/5=5/5z`

But `5/5=1`

`8/5=z`

Write as: `z=8/5`