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3 years ago

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

Mathematics

1 answer:

sveticcg [70]3 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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<u>Answer:</u>

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multiply eq(2) by 3, we get

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Subracting (3) from (4)

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(-) (-) (-)

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0x + y = 10

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Read 2 more answers

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?