Please show your work and help

Mathematics

1 answer:

Levart [38]2 years ago

8 0

Answer:

22.5 cm

Step-by-step explanation:

An equilateral triangle has 3 equal sides

perimeter is the sum of all 3 sides, hence

perimeter = 3 × 7.5 = 22.5 cm

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Which equation can be used to find the area of trapezoid PQRT?

vladimir2022 [97]

Answer:

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Step-by-step explanation:

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2 years ago

What is the solution problem for x=9.81.

mixer [17]

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2 years ago

Will mark brainliest! Questions are in the picture!

alexdok [17]

Answer:

52.9 inches .

Step-by-step explanation:

Given that the triangular indentation has an area of 100 in.² and the base and height of this traingle are represented by expressions 3x and x+3 respectively . We need to find out the perimeter to the nearest tenth.

As we know that the area of triangle is ,

$\rm\longrightarrow Area_{\triangle}=\dfrac{1}{2}(base)(height)$

Substituting the respective values,

$\rm\longrightarrow 100\ =\dfrac{1}{2}(x+3)(3x)\\\\\rm\longrightarrow 2(100) = 3x(x+3)\\\\\rm\longrightarrow200 = 3x^2+9x\\\\\rm\longrightarrow 3x^2+9x-200=0$

On using the Quadratic formula , we have;

$\rm\longrightarrow x =\dfrac{-9\pm\sqrt{9^2-4(3)(-200)}}{2(3)} \\\\\rm\longrightarrow x =\dfrac{-9\pm \sqrt{81+1200}}{6}\\\\\rm\longrightarrow x =\dfrac{-9\pm \sqrt{1281}}{6}$