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What is the value of x for each question? Step by step please.

-1/2-4x/5=1/2-2x

7x²+9x²=-6x²-7x

-7x²+6=x²-7x²

1 Answer

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Answer:

-1/2-4x/5=1/2-2x

Starting from the left side, we can simplify:

-1/2 - 4x/5 = 1/2 - 2x

Next, we can isolate x by adding 2x to both sides:

-1/2 - 4x/5 + 2x = 1/2 - 2x + 2x

-1/2 + 2x/5 = 1/2

Adding 1/2 to both sides:

0 + 2x/5 = 1

Finally, solving for x:

2x/5 = 1

Multiplying both sides by 5:

2x = 5

Dividing both sides by 2:

x = 5/2

7x² + 9x² = -6x² - 7x

Combining like terms:

16x² = -6x² - 7x

Adding 6x² to both sides:

22x² = -7x

Dividing both sides by -7:

-22x²/-7 = 7x/-7

-22x²/7 = -7x/7

-22x²/7 = -x

Multiplying both sides by -7:

22x² = x

Dividing both sides by 22:

x² = x/22

Since this equation states that x² equals x divided by 22, it has no real solutions for x.

-7x² + 6 = x² - 7x²

Combining like terms:

-8x² + 6 = 0

Adding 8x² to both sides:

-8x² + 8x² + 6 = 0 + 8x²

6 = 8x²

Dividing both sides by 8:

6/8 = 8x²/8

3/4 = x²

Taking the square root of both sides:

sqrt(3/4) = sqrt(x²)

x = +/- sqrt(3/4)

User Ryan Tenney
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