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2 years ago

Evaluate 3x^2 - x for x = -2

Mathematics

1 answer:

Butoxors [25]2 years ago

4 0

Answer:

$3x^2 - x$

$3 \times - 2 \times - 2 - 2$

$(3 \times - 2 \times - 2) - ( - 2)$

$12 + 2 = 14$

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RSB [31]

Step-by-step explanation:

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2 years ago

7(3r - 1) - (r + 5) = -52 Please step by step help

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3 years ago

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An open box with a square base is constructed so that it has a volume of 64in^3. The base needs to be made out of a material tha

Ivahew [28]

The volume of a box is the amount of space in the box

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$x^3 = 64$

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2 years ago

A triangle has three angles. The first angle measures 20 less than a number. The second triangle is three

abruzzese [7]

Answer:

first angle is 20, 2nd is 120, 3rd is 40.

Step-by-step explanation:

with these words, "20 less than a number, Three

times the number, is the number." We can set up the equation x-20+3x+x = 180. combine like terms and we get 5x-20=180. add 20 to both sides to get 5x=200 then divide 200 by 5x to get x = 40. We can then plug 40 into each of the expressions, x-20, 3x, x, to get our angles.

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2 years ago

Evaluate 3x^2 - x for x = -2​

Evaluate 3x^2 - x for x = -2