Question

The side of an equilateral triangle is 12. Its area is

Select one:
a. 144
b. 72
c. 36 √3
d. 48

Answer 1

Answer: Choice C.
`36√(3)`

This is the same as writing 36*sqrt(3)

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Work Shown:

x = 12 = side length of equilateral triangle

A = area of equilateral triangle

A = 0.25*sqrt(3)*x^2

A = 0.25*sqrt(3)*12^2

A = 0.25*sqrt(3)*144

A = 0.25*144*sqrt(3)

A = 36*sqrt(3) .... answer is choice C

Side note: the area approximates to 62.354 square units.

Answer 2

area is 1/2bh

in an euqilateral triangle, all sides are equal so base and height are 12

1/2 x 12 x 12

1/2 x 144= 72 (B)