Find the area of an isosceles triangle with perimeter of 40 feet and a base of 12 feet. Round to the nearest whole number.

Mathematics

1 answer:

Aleksandr [31]3 years ago

5 0

Answer: 76 ft2

Step-by-step explanation:

Perimeter = 2 side length +base length

40 = 2s +12

Solving for s:

40-12 =2s

28 =2s

28/2=s

14ft =side

Since the line which bisects and isosceles triangles is at a right angle to the base we can use the Pythagorean Theorem to find the height (see attachment)

c^2 = a^2 + b^2

Where c is the hypotenuse of the triangle (in this case 14) and a and b are the other sides. (Base divided by 2 is one side, the other side is the height)

Replacing with the values given:

14^2= 6^2 + x^2

196 = 36 + x^2

196-36 = x^2

160 = x^2

√160 = x

x = 12.64 (height)

Area of an isosceles triangle = 1/2 x base x height

A = 1/2 x 12 x 12.64 = 76 ft2

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Answer:

0.66

Step-by-step explanation:

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8 0

3 years ago

A simplifie 6 × ( - 24 ) ÷ ( -4 )

kumpel [21]

$\huge\textbf{Hey there!}$

$\huge\boxed{\mathsf{6\times(-24)\div (-4)}}\\\huge\boxed{= \mathsf{\dfrac{6(-24)}{-4}}}\\\huge\boxed{\mathsf{= \dfrac{\bold{-144}}{-4}}}\\\huge\boxed{\mathsf{\dfrac{-144\div-4}{-4\div-4}}}\\\huge\boxed{= \mathsf{\dfrac{\bold{36}}{1}}}\\\huge\boxed{\mathsf{= 36\div1}}\\\huge\boxed{\mathsf{= 36}}\\\\\\\huge\text{\bf Therefore, your answer is: \boxed{\mathsf{36}}}\huge\checkmark$