Answer:
2a +2b +4
Step-by-step explanation:
The perimeter is the sum of the lengths of the three sides. If x represents the length of the third side, then ...
(3a +8) +(5a +b) +x = (10a +3b +12)
Subtracting from the equation everything on the left side that is not x, we get ...
x = (10a +3b +12) -(3a +8) -(5a +b)
= a(10 -3 -5) +b(3 -1) +(12 -8)
= 2a +2b +4
The length of the third side is 2a +2b +4.
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Given:
The radius of the base of the given cone = 5 cm
The slant height of the cone = 19 cm
To find the surface area of the given cone.
Formula
The surface area pf the given cone is,
where, r be the radius and
l be the slant height.
Now,
Taking, r = 5, l = 19 and π = 3.14 we get,
sq cm
or, sq cm
or, sq cm
Rounding off to the nearest square centimeter, we get;
Hence,
The surface area of the cone is 377 sq cm.