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2 years ago

8

A) The cosine rule can be used to find the value of x in the triangle below.

1 answer:

BartSMP [9]2 years ago

5 0

Answer:

see explanation

Step-by-step explanation:

(a)

(the side required )² = sum of squares of other 2 sides - ( 2 × product of other 2 sides and cos(angle opposite side required ) )

x² = 12² + 15² - (2 × 12 × 15 × cos71°)

(b)

x² = 144 + 225 - 360cos71°

= 369 - 360cos71° ( take square root of both sides )

x = $\sqrt{369-360cos71}$

≈ 16 cm ( to the nearest integer )

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Answer:

The equation of the line is,

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Step-by-step explanation:

First, you have to write it in a form of y = mx + b :

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$y = 3 - \frac{2}{5} x$

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When both lines are parallel to each other, they will have to same gradient value. So the equation of the line is y = (-2/5)x + b. Next, you have to find the value of b by substutituting (-10,3) into the equation :

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3 years ago

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3 years ago

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3 years ago

Use the exponential decay model, Upper A equals Upper A 0 e Superscript kt, to solve the following. The half-life of a certai

Akimi4 [234]

Answer:

It will take 7 years ( approx )

Step-by-step explanation:

Given equation that shows the amount of the substance after t years,

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3 years ago

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masya89 [10]

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