Answer:
lateral surface area =118.42
Step-by-step explanation:
y= 9x/7
dx/dy =
Given x range as from 0 ≤ x ≤ 7 ⇒ The range of x is
a= 9x/7 = 9(0)/4 = 0
b = 9x/7= 9(7)/4 = 9
lateral surface area of the cone
[tex]\int\limits^b_a {2\pi x\sqrt{1 + (\frac{dx}{dy} })^2 } \, dx \\\\\int\limits^9_0 {2\pi (\frac{9x}{7} )\sqrt{1 + (\frac{9}{7} })^2 } \, dx[/tex]
=[tex]\frac{18\pi \sqrt{130} }{49} \int\limits^9_0 {x} \, dx \\[/tex]
=118.42