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3 years ago

3(x + 5) = 7x - 13

Mathematics

1 answer:

attashe74 [19]3 years ago

6 0

Answer:

Distributive

Step-by-step explanation:

3(x + 5) = 7x - 13 given

3x + 15 = 7x - 13 distribute

- 3x -3x Subtraction property of equality

15= 7x - 13

+13 +13 Addition property of equality

28 = 7x

7 7 division property of equality

4=x simplify

x=4

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b. 0.0722

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Step-by-step explanation:

Let b and h denote the base and height as indicated in the diagram. By pythagoras theorem, $h^2 + b^2 = 16^2 = 256 \dotsc\;(1)$ because it is a right angle triangle.

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b. From the diagram, infer that $16 \sin{\theta} = b$ . When b = 8, then $\theta = \arcsin{0.5} = \ang{30}$ .

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