A cone 3

A cone has a diameter of x cm and a slant height of y cm. A square pyramid has a base side length of x cm and a slant height of y cm. Which has the greater surface area? Explain.

Correct answer:

x = pyramid

Step-by-step explanation:

$$\begin{gathered} S_1=\pi \cdot (x/2{)}^2=\pi /4\cdot x^2 \\ {S}_2=x^2 \\ {S}_{2}vs{S}_1 \\ {x}^2>\pi /4x^2 \\ 1>0.78539816 \\ {S}_2>S_1 \\ {S}_3=\pi \cdot (x/2)\cdot y=\pi /2\cdot xy \\ {S}_4=4\cdot x\cdot y/2=2\cdot xy \\ {S}_{4}vs{S}_3 \\ 2\cdot xy>\pi /2\cdot xy \\ 2>\pi /2 \\ 2>1.57079633 \\ {S}_4>S_3 \\ x=p_{y}ramid \end{gathered}$$

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