To multiply or divide radicals, multiply or divide the coefficients and radicands separately: \(x\sqrt{a} \times y\sqrt{b} = xy\sqrt{ab}\) and \({x\sqrt{a} \over y\sqrt{b}} = {x \over y}\sqrt{a \over b}\)
What is 4\( \sqrt{7} \) x 9\( \sqrt{4} \)?
| 36\( \sqrt{4} \) | |
| 13\( \sqrt{7} \) | |
| 13\( \sqrt{28} \) | |
| 72\( \sqrt{7} \) |