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3 years ago

Solve the system by the elimination method.

Mathematics

1 answer:

katovenus [111]3 years ago

4 0

C. (-4,-⅔)

Step-by-step explanation:

Elimination Method:

R - 9S = 2

3R - 3S = -10

I'll solve for X first by eliminating S.

R - 9S = 2

-3(3R - 3S = -10)

R - 9S = 2

-9R + 9S = 30

(Add the equations)

-9R = 32

(Divide both sides by -9)

-9R/-5 = 32/-5

R = -4

Substitute the R value into either equation:

R - 9S = 2

(-4) - 9S = 2 (Add 4 to both sides of the equation)

+4 +4

-9S = 6 (Divide both sides of the equation by -9)

-9S/-9 = 6/-9

S = -6/9

Simplify

S = -2/3

Solution: (-4,-⅔)

Hope this helped

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3 years ago

What is the value of f?<br><br> 6f−12=−4f+6

Xelga [282]

First you had to add by twelve from both sides of equation form.

$6f-12+12=-4f+6+12$

Then simplify.

$6f=-4f+18$

Next, add by four-f from both sides of equation form.

$6f+4f=-4f+18+4f$

Simplify.

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Final answer: $\boxed{f=9/5}$

Hope this helps!

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3 years ago

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3 years ago

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stich3 [128]

Answer:

$x = 1 + \sqrt{2} \ \ or \ 1- \sqrt{2}$

Step-by-step explanation:

Given;

x² - 2x - 1 = 0

Solve by completing the square method;

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⇒ square half of coefficient of x and add it to the both sides of the equation

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Therefore, option B is the right solution.

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3 years ago