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Rama09 [41]
2 years ago
12

Solve the equation 7x^2+21=0

Mathematics
1 answer:
Radda [10]2 years ago
6 0
Subtract 21 from both sides
7x^2=-21
Divide by seven on both sides
X^2=-3
Square root both sides

***X= square root of -3***
:)
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Step-by-step explanation:

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add the term that makes the given expression into a perfect square. write the result as the square of a bracketed expression c s
Molodets [167]
<h2>Perfect Squares</h2>

Perfect square formula/rules:

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Trinomials are often organized like ax^2+bx+c.

The <em>b</em> value in this case is <em>c</em>, and it will always equal the square of half of the <em>b</em> value.

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<h2>Solving the Question</h2>

We're given:

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In a trinomial, we're given the ax^2 and bx values. <em>a</em> in this case is 1 and <em>b</em> in this case is 4. To find the third value by dividing 4 by 2 and squaring the quotient:

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Therefore, the term that we can add is + 4.

c^2-4c+4

To write this as the square of a bracketed expression, we can follow the rule a^2-2ab+b^2=(a-b)^2:

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4 0
1 year ago
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(a + b)(a² - ab + b²)

Each term in the second factor is multiplied by each term in the first factor, that is

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velikii [3]

Step-by-step explanation:

given,

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x=?

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x= find yourself

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2 years ago
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fredd [130]

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Therefore, the correct answer is 2/3πx³.

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