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3 years ago

3. "a varies directly with b". If a = 4 when b = 21, find a when b-7.

Mathematics

2 answers:

Irina-Kira [14]3 years ago

8 0

Step-by-step explanation:

A(promotional sign)b

A=kb

4=21k

K=0. 1904

A=0. 2b

A=0. 2×7

A=1. 4

goldfiish [28.3K]3 years ago

7 0

Step-by-step explanation:

a varies directly with b

a ∞ b

a = Kb

K is the constant of proportionality

If a = 4 when b = 21

4 = 21×k

4 = 21k

k = 4/21

: - a = 4b/21

find a when b= 7.

a = 4(7)/21

a = 4/3

a = 1 1/3

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-3 \cdot f(-8) + 7 \cdot g(2) =−3⋅f(−8)+7⋅g(2)=minus, 3, dot, f, left parenthesis, minus, 8, right parenthesis, plus, 7, dot, g,

dsp73

Answer:

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Step-by-step explanation:

The graph from which the information is to be read is attached below.

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2 years ago

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Inga [223]

9514 1404 393

Answer:

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Step-by-step explanation:

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y-values increase by 3 from row to row.

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m = ∆y/∆x = 3/1 = 3

The only offered choice with an x-coefficient of 3 is ...

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2 years ago

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Answer:

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Step-by-step explanation:

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$tan(60^o)=\frac{opposite}{adjacent} \\\sqrt{3} =\frac{y}{10} \\y=10\,\sqrt{3}$

and also:

$cos(60^o)=\frac{adjacent}{hypotenuse}\\\frac{1}{2} =\frac{10}{x}\\x=20$

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2 years ago