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3 years ago

Is 7x - 5 =2x + 8 true when x =2

Mathematics

2 answers:

mylen [45]3 years ago

8 0

Answer:

Step-by-step explanation:

Plug in 2 for x

7(2) - 5 = 2(2) +8

14 -5 = 4 + 8

9 = 12

9 does not equal to 12, which means it's not true.

svetlana [45]3 years ago

4 0

Answer:

No its not true

Step-by-step explanation:

(7x2)-5= 14-5= 9

(2x2)+8= 4+8= 12

9=12

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jonny [76]

Answer:

x = -9/22 or -0.409 to the nearest thousandth.

Step-by-step explanation:

Cross multiplying we get:

(3x + 1)(x - 5) = (3x + 2)(x + 2)

3x^2 - 14x - 5 = 3x^2 +8x + 4

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x = -9/22

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Step-by-step explanation:

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Answer:

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Step-by-step explanation:

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2 years ago

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Step-by-step explanation:

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1 year ago

7-18 use part 1 of the fundamental theorem of calculus to find the derivative of the function.

blondinia [14]

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$\cfrac{dh}{dx}\implies \displaystyle \cfrac{d}{du}\left[ \int\limits_{1}^{u}~\cfrac{z^2}{z^4+1}dz \right]\cdot \cfrac{1}{2\sqrt{x}}\implies \left[ \cfrac{u^2}{u^4+1} \right]\cdot \cfrac{1}{2\sqrt{x}} \\\\\\ \stackrel{substituting~back}{\left[ \cfrac{(\sqrt{x})^2}{(\sqrt{x})^4+1} \right]\cdot \cfrac{1}{2\sqrt{x}}}\implies \cfrac{x}{x^2+1}\cdot \cfrac{1}{2\sqrt{x}}\implies \cfrac{\sqrt{x}}{2x^2+2}$

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1 year ago