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2 years ago

Slove x^2-8x=20 by completing the square. which is the solution set of equation?

Mathematics

1 answer:

sveticcg [70]2 years ago

3 0

x^2-8x=20

Move +20 to the other side. Sign changes from +20 to -20

x^2-8x-20=20-20

x^2-8x-20=0

Think about two numbers that equals to -20 and -8.

(x-10)(x+2)=0

x-10=0 ( move -10 to the other side). Sign changes from -10 to 10

x-10+10=0+10

x=10

x+2=0 ( move +2 to the other side). Sign changes from +2 to -2

x+2-2=0-2

x=-2

Answer:

x=10, x=-2

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Answer:

B. -6

Step-by-step explanation:

The common difference here is the difference between each term. Since it is an arithmetic sequence the difference between each term will be the same value.

So, from 45 (the 1st term) to 39 (the 2nd term), the difference is -6

From 39(the 2nd term) to 33, the difference is also -6.

Therefore, we know that the common difference fro this arithmetic sequence is -6.

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2 years ago

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Answer:

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Step-by-step explanation:

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6 containers needed

Step-by-step explanation:

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2 years ago

A building across the street casts a shadow that is 24 feet long your friend is 6 feet tall and casts a shadow that is 4 feet lo

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natita [175]

Answer:

$12\sin{(2\theta)}\cos{(\theta)}$

Step-by-step explanation:

The appropriate trig identity is ...

$\sin{a}+\sin{b}=2\sin{\left(\dfrac{a+b}{2}\right)}\cos{\left(\dfrac{a-b}{2}\right)}$

Here, you have a scale factor of 6 and a=3θ, b=θ. Filling in these values gives ...

$6\sin{3\theta}+6\sin{\theta}=12\sin{\left(\dfrac{3\theta+\theta}{2}\right)}\cos{\left(\dfrac{3\theta-\theta}{2}\right)}\\\\=12\sin{(2\theta)}\cos{(\theta)}$

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2 years ago

Slove x^2-8x=20 by completing the square. which is the solution set of equation?​

Slove x^2-8x=20 by completing the square. which is the solution set of equation?