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2 years ago

6

If the perimeter of an equilateral triangle is 30cm, find its area.

1 answer:

lora16 [44]2 years ago

7 0

Answer:

A ≈ 43.3 cm²

Step-by-step explanation:

the area (A) of an equilateral triangle is calculated as

A = $\frac{s^2\sqrt{3} }{4}$ ( s is a side of the triangle )

given perimeter = 30 cm , then

s = 30 cm ÷ 3 = 10 cm

then

A = $\frac{10^2\sqrt{3} }{4}$ = $\frac{100\sqrt{3} }{4}$ = 25 $\sqrt{3}$ ≈ 43.3 cm² ( to the nearest tenth )

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3 years ago

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Step-by-step explanation:

We know that any sphere can be represented by the following equation:

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If $(h,k, s) = (-2,3,7)$ and $r = 7$ , we obtain this expression:

$(x+2)^{2}+(y-3)^{2}+(z-7)^{2} = 49$

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Step-by-step explanation:

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FromTheMoon [43]

<u>Given</u>:

Given that the two linear equations in the graph are $y=-3x+6$ and $y=2x-4$

We need to determine the number of solutions can be determined from the system of linear equations.

<u>Solutions:</u>

The number of solutions to the system of linear equations can be determined using the substitution method.

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Hence, the solution to the system of linear equations is (2,0)

Therefore, the system of equations have one solution.

Thus, Option B is the correct answer.

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