Kite rhombus calculation

The dragon is shaped like a diamond. Its diagonals are 60 cm and 90 cm long. Calculate:
a) side of the rhombus
b) how much paper do we need to make the kite? If we need to stick it on both sides, it needs 5% of the total area of the paper to bend.

Final Answer:

a =  54.0833 cm
S =  2835 cm²

Step-by-step explanation:

$$\begin{gathered} u=60\text{cm} \\ v=90\text{cm} \\ a=\sqrt{(u/2{)}^2+(v/2{)}^2}=\sqrt{(60/2{)}^2+(90/2{)}^2}=15\sqrt{13}=54.0833\text{cm} \end{gathered}$$

$$\begin{gathered} q=100\%+5\%=1+\frac{5}{100}=1.05 \\ S=\frac{u\cdot v}{2}\cdot q=\frac{60\cdot 90}{2}\cdot \frac{21}{20}=2835{\text{cm}}^2 \end{gathered}$$

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