Question

Substitute equation (2) into (1) to give a new equation for p that involves only I and R

Re arrange (2) to make I the subject, and substitute your result into equation (1) to give a new equation containing only V and R

Answer 1

`p = {i}^(2) r`

`i = \sqrt{ (p)/(r) }`

P= VI

V= IR

Substitute eqn 1 into eqn 2

P= (IR) I

`p = {i}^(2) r`

`(p)/(r) = \frac{ {i}^(2)r }{r}`

`{i}^(2) = (p)/(r)`

`i = \sqrt{ (p)/(r) }`