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3 years ago

Which equations are correct

Mathematics

1 answer:

VARVARA [1.3K]3 years ago

3 0

Answer:

2nd, 3rd and 4th equations are correct.

Step-by-step explanation:

$-4x^2(2x^2+5)=-8x^4-20x^2\\\\$

is right because each term inside is multiplied by -4x square and we find the answer is right.

$-4b^3(5b^2+3)\\\\\\= -4(5)(b^3)(b^2) =-20b^6-12b^3\\$

Hence correctly done.

$-5a^4(2a^2+4)= (-5)(2)(a^4)(a^2)+(-5)(4)(a^4\\-10a^6-20a^4\\$

Correctly done.

$-6^4(4y^2+2)=-24y^8-12y^4\\= -(6)(6)(6)(6) 4y^2 -(6)(6)(6)(6) (2)$

should be the right answer.

But instead only 6 is multiplied by inner terms. Hence wrong.

I answer is wrong and others are right.

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Mrs. Kellen's most recent math test consisted of 50 questions. Some of the questions were worth two points and the rest of the q

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Answer:

The answer to your question is: 35 questions worth 2 points and 15 questions worth 3 points.

Step-by-step explanation:

Data

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y = questions worth 3 points

Process

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Answer:

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Step-by-step explanation:

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Dividing both sides by 0.05

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