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lilavasa [31]
2 years ago
12

Suppose y =2x+10. Find Y if x=4 Suppose Y = 2x - 4. Find X if y=10

Mathematics
1 answer:
Zepler [3.9K]2 years ago
7 0
You just have to plug in the value of x and y.
1) y = 2x + 10 —> y = 2(4) + 10
y = 8 + 10
y = 18
2) y = 2x - 4 —> 10 = 2x - 4
add four to both sides
14 = 2x and divide 2 by both sides and you get x = 7
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Answer:

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Evaluate Algebraic Expressions

In the last section, we simplified expressions using the order of operations. In this section, we’ll evaluate expressions—again following the order of operations.

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Solution

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x+7

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exercise 2.3.1

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Answer a

Answer b

exercise 2.3.2

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Answer b

Example 2.3.2

Evaluate 9x−2, when

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Remember ab means a times b, so 9x means 9 times x.

To evaluate the expression when x=5, we substitute 5 for x, and then simplify.

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Substitute 5 for x.

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Multiply.

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Subtract.

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To evaluate the expression when x=1, we substitute 1 for x, and then simplify.

9x−2

Substitute 1 for x.

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exercise 2.3.3

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exercise 2.3.4

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Example 2.3.3: evaluate

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exercise 2.3.8

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Example 2.3.5: evaluate

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Answer

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Example 2.3.6: evaluate

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