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4 years ago

2x-y=4 and 7x+3y=27 step by step

Mathematics

1 answer:

aalyn [17]4 years ago

4 0

Answer:

x=3 y=2

Step-by-step explanation:

2x-y=4

7x+3y=27

Multiply the first equation by 3

3(2x-y)=4*3

6x - 3y+12

Add this to the second equation to eliminate y

6x -3y = 12

7x+3y=27

---------------------

13x +0y = 39

Divide each side by 13

13x/13 = 39/13

x = 3

Now find y

2x-y =4

2(3) -y = 4

6-y=4

Subtract 6 from each side

6-y-6 = 4-6

-y = -2

y=2

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If you are solving the equation 1/(x-4)+1=14/(x+2) by factoring, which of the following equations would you use the zero product

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Answer:

The equation that would be used for the zero product property on will be (x-5)(x-10)=0

Option B is correct.

Step-by-step explanation:

We need to solve the equation $\frac{1}{(x-4)}+1=\frac{14}{x+2}$

Solving the equation:

$\frac{1}{(x-4)}+1=\frac{14}{x+2}\\\frac{1+(x-4)}{x-4}= \frac{14}{x+2}\\\frac{1+x-4}{x-4}= \frac{14}{x+2}\\\frac{x-3}{x-4}= \frac{14}{x+2}\\Cross\: Multiply\\(x-3)(x+2)=14(x-4)\\x(x+2)-3(x+2)=14x-56\\x^2+2x-3x-6=14x-56\\x^2-x-6-14x+56=0\\x^2-x-14x-6+50=0\\x^2-15x+50=0$

Now, we would factorise to find value of x

$x^2-15x+50=0\\x^2-5x-10x+50=0\\x(x-5)-10(x-5)=0\\(x-5)(x-10)=0$

So, the equation that would be used for the zero product property on will be (x-5)(x-10)=0

Option B is correct.

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2 years ago

Please help me do this

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Answer:

Step-by-step explanation:

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(3x + 1)(x - 3) = x Remove the brackets. Use FOIL

f:3x*x = 3x^2

o:3x*(-3) = -9x

i:1*x = x

L : 1 * - 3 = -3

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3x^2 - 8x -x - 3 = 0 Combine

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3 years ago