Find the surface area of the cone. Use 3.14 for
π
D-8
h-7
the slant height s is found by s^2 = 4^2 + 7^2
(draw a side view to see this)
Now, just use your area formula
a = πr^2 + πrs
pls help
diameter is 8 and height is 7
will someone help me
To find the surface area of a cone, we need the values of the radius (r) and the slant height (l). The given information, D = 8, represents the diameter of the base of the cone. To find the radius (r), we divide the diameter by 2.
r = D/2
r = 8/2
r = 4
The slant height (l) can be obtained using the Pythagorean theorem, utilizing the height (h) and the radius (r) of the cone.
l = √(r^2 + h^2)
l = √(4^2 + 7^2)
l ≈ √(16 + 49)
l ≈ √65
l ≈ 8.06
Now that we have the radius (r = 4) and the slant height (l ≈ 8.06) of the cone, we can calculate the surface area (A) using the formula:
A = π * r * (r + l)
Given that we should use 3.14 for π:
A ≈ 3.14 * 4 * (4 + 8.06)
A ≈ 3.14 * 4 * 12.06
A ≈ 150.796
Therefore, the surface area of a cone with D = 8 and h = 7 is approximately 150.796 square units.