Question

Please help me. The answer in the booklet says it’s R=3, but I need working out because I don’t get it.

Answer 1

3.

Explanation:

R = √[(2)^2 + (√5)^2]

= √(4 + 5)

= √9

= 3.

Answer 2

3

Explanation:

`R =\sqrt{a^(2)+b^(2)}\\\\= \sqrt{2^(2)+(√(5))^(2)}\\\\= √(4+5)\\\\=√(9)\\\\= √(3*3)\\\\= 3`

Hint: (√5)² =
`√(5)*√(5) = √(5*5)=5`