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2 years ago

Evaluate the following expression if x = -7. 3x2 - 4x + 5

Mathematics

1 answer:

Tanzania [10]2 years ago

6 0

3 ×2 - 4(-7) + 5

3 × 2 +28 + 5

6 + 28 +5

=39

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Given:

Expression is

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To prove:

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Step-by-step explanation:

Property 1: Every integer is a rational number. It is Theorem 4.3.1.

Property 2: The sum of any two rational numbers is rational. It is Theorem 4.3.2.

Property 3: The product of any two rational numbers is rational. It is Exercise 15 in Section 4.3.

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It can be written as

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Now,

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Hence proved.

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