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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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To make this problem solvable, I have replaced the 't' in the second equation for a 'y'.

Answer:

x = -9

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Step-by-step explanation:

Solve the system:

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2x + y = -16 [2]

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3y - y = -12 + 16

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1 year ago

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Nat2105 [25]

Answer:

(0,-4) (5,0)

Step-by-step explanation:

4x-5y=20

First, we must put the equation into slope intercept form: y= mx+b

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The y intercept, by definition, is b. In this scenario, b is -4.

One ordered pair that works is (0,-4).

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0=4/5(x)-4= 4=4/5x
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Therefore, (5,0) works as well!

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2 years ago

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Answer:

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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?