Question

If $5a+2b=0$ and $a$ is two less than $b$, what is $7b$?

Answer 1

7b = 10

Explanation:

We have that:

5a + 2b = 0

a is two less than b

So a = b - 2.

Replacing in the above equation:

`5a + 2b = 0`

`5(b - 2) + 2b = 0`

`5b - 10 + 2b = 0`

`7b = 10`

`b = (10)/(7)`

7b

`7b = 7(10)/(7) = (70)/(7) = 10`

7b = 10