Question

How do you simplify `2sqrt98-4sqrt18`?

Answer 1

`2sqrt2`

Explanation:

factorise 98 and 18
`98= 2×7×7`
`sqrt98=7sqrt2`

`18=3×3×2`
`sqrt18=3sqrt3`

`2sqrt98=2×7sqrt2=14sqrt2`.
`4sqrt18=4×3sqrt2=12sqrt2`.
subtract;
`14sqrt2-12sqrt2=2sqrt2`.
`2sqrt2= 2.8284271247`
Hope it helps