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Citrus2011 [14]

3 years ago

6

Todd has 21 white tiles dnd some black tiles to make a mosaic. The mosaic has a total area of 144 Square centimeters. Each tile

has an area of 3 square. How many black tiles did Todd use?

1 answer:

tekilochka [14]3 years ago

3 0

Answer:the number of black tiles that Todd used is 27

Step-by-step explanation:

Let x represent the number of black tiles that Todd used.

Todd has 21 white tiles and some black tiles to make a mosaic. Each tile has an area of 3 square. It means that the total area of the white tiles is 21 × 3 = 63 cm^2

The total area of the white tiles is x × 3 = 3x cm^2

The mosaic has a total area of 144 Square centimeters. It means that

3x + 63 = 144

3x = 144 - 63 = 81

x = 81/3 = 27

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Step-by-step explanation:

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For the parabola in the problem, we know that the vertex has coordinates (4,-3), so we have:

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step 1

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step 2

Find the distance BC

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substitute in the formula

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step 3

Find the distance AC

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substitute in the formula

$AC=\sqrt{(-2-1)^{2}+(1+3)^{2}}$

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step 4

Find the perimeter

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substitute the values

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