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3 years ago

10

Ifa-b=4 and a^2- b^2=3, what is the value of a+b?

1 answer:

kiruha [24]3 years ago

5 0

Answer:

$\large\boxed{a+b=\dfrac{3}{4}}$

Step-by-step explanation:

$\text{Use}\ a^2-b^2=(a-b)(a+b).\\\\\text{We have}\ a-b=4\ \text{and}\ a^2-b^2=3.\\\\\text{Substitute:}\\\\3=4(a+b)\qquad\text{divide both sides by 4}\\\\\dfrac{3}{4}=(a+b)\to a+b=\dfrac{3}{4}$

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OlgaM077 [116]

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... 30-60-90: 1 : √3 : 2

... 45-45-90: 1 : 1 : √2

The long side of ΔMDX is 10√3, so the other two sides are

... MX = MD(√3/2) = 15

... DX = MD(1/2) = 5√3

The short side of ΔMNX is MX = 15, so the other two sides are

... NX = MX(1) = 15

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Then the perimeter of ΔDMN is ...

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... P = 10√3 +15√2 + 15 + 5√3

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3 years ago

Lin runs 8 laps around a track in 26 minutes.

lyudmila [28]

Answer:

Step-by-step explanation:

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3 years ago

Use any method to multiply (3a + 2b - c)(a - b + 2c).

Alla [95]

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Step-by-step explanation:

(3a + 2b − c) (a − b + 2c)

Expand (3a + 2b − c) (a − b + 2c) by multiplying each term in the first expression by each term in the second expression.

3a ⋅ a + 3a (−b) + 3a (2c) + 2ba + 2b (−b) + 2b (2c) − ca − c (−b) − c (2c)

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Rewrite using the commutative property of multiplication.

3a^2 + 3 ⋅ −1ab + 3a (2c) + 2ba + 2b (−b) + 2b (2c) − ca − c (−b) − c (2c)

3a^2 − 3ab + 3a (2c) + 2ba + 2b (−b) + 2b (2c) − ca − c (−b) − c (2c)

Rewrite using the commutative property of multiplication.

3a^2 − 3ab + 3 ⋅ 2ac + 2ba + 2b (−b) + 2b (2c) − ca − c (−b) − c (2c)

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Rewrite using the commutative property of multiplication.

3a^2 − 3ab + 6ac + 2ba + 2 ⋅ −1b ⋅ b + 2b (2c) − ca − c (−b) − c (2c)

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Rewrite using the commutative property of multiplication.

3a^2 − 3ab + 6ac + 2ba − 2b^2 + 2 ⋅ 2bc − ca − c (−b) − c (2c)

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Rewrite using the commutative property of multiplication.

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Rewrite using the commutative property of multiplication.

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3a^2 − ab − 2b^2 + 4bc + bc + 5ac − 2c^2

3a^2 − ab − 2b^2 + 5bc + 5ac − 2c^2

3a^2 − ab − 2b^2 + 5ac + 5bc − 2c^2

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3 years ago

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fenix001 [56]

Answer:

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Step-by-step explanation:

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3 years ago

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konstantin123 [22]

Answer:

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Step-by-step explanation:

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6 0

3 years ago