Question

Any one know who to do surds

Answer 1

7
`√(7)`

Explanation:

using the law of surds

`√(a)` ×
`√(b)` ⇔
`√(ab)`

simplifying each surd

`√(700)` =
`√(100(7))` =
`√(100)` ×
`√(7)` = 10
`√(7)`

`√(28)` =
`√(4(7))` =
`√(4)` ×
`√(7)` = 2
`√(7)`

Putting it all together gives

10
`√(7)` - 2
`√(7)` -
`√(7)` = 7
`√(7)`