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solve each equation. 1. \\(\\frac{1}{x + 4} = 5\\) 2. \\(\\frac{1}{x - …

Question

solve each equation.

  1. \\(\frac{1}{x + 4} = 5\\)
  2. \\(\frac{1}{x - 3} = 6\\)
  3. \\(\frac{1}{2x - 3} + \frac{1}{5 - 2x}\\)
  4. \\(2 - \frac{1}{x + 3} = \frac{1}{x + 3}\\)
  5. \\(\frac{1}{x + 3} + \frac{1}{x - 3} = \frac{6}{x^2 - 9}\\)
  6. \\(\frac{4}{x + 2} = \frac{x^2}{x + 2}\\)

Explanation:

Problem 1: Solve \(\boldsymbol{\frac{1}{x + 4}=5}\)

Step 1: Multiply both sides by \(x + 4\)

To eliminate the denominator, we multiply both sides of the equation \(\frac{1}{x + 4}=5\) by \(x + 4\) (assuming \(x
eq - 4\) to avoid division by zero).

$$ \frac{1}{x + 4}\times(x + 4)=5\times(x + 4) $$

This simplifies to:

$$ 1 = 5(x + 4) $$

Step 2: Expand the right - hand side

Using the distributive property \(a(b + c)=ab+ac\), where \(a = 5\), \(b=x\) and \(c = 4\), we get:

$$ 1=5x+20 $$

Step 3: Solve for \(x\)

Subtract 20 from both sides of the equation:

$$ 1-20=5x+20 - 20 $$
$$ - 19 = 5x $$

Then divide both sides by 5:

$$ x=-\frac{19}{5}=-3.8 $$

We need to check if this solution makes the original denominator non - zero. When \(x =-\frac{19}{5}\), \(x + 4=-\frac{19}{5}+4=-\frac{19}{5}+\frac{20}{5}=\frac{1}{5}
eq0\). So the solution is valid.

Step 1: Multiply both sides by \(x - 3\)

Multiply both sides of the equation \(\frac{1}{x - 3}=6\) by \(x - 3\) (assuming \(x
eq3\) to avoid division by zero).

$$ \frac{1}{x - 3}\times(x - 3)=6\times(x - 3) $$

This simplifies to:

$$ 1 = 6(x - 3) $$

Step 2: Expand the right - hand side

Using the distributive property \(a(b - c)=ab - ac\), where \(a = 6\), \(b=x\) and \(c = 3\), we get:

$$ 1=6x-18 $$

Step 3: Solve for \(x\)

Add 18 to both sides of the equation:

$$ 1 + 18=6x-18 + 18 $$
$$ 19 = 6x $$

Divide both sides by 6:

$$ x=\frac{19}{6}\approx3.17 $$

Check the denominator: When \(x=\frac{19}{6}\), \(x - 3=\frac{19}{6}-\frac{18}{6}=\frac{1}{6}
eq0\). So the solution is valid.

Step 1: Notice the relationship between denominators

We can rewrite \(5 - 2x\) as \(-(2x - 5)=-(2x-3 + 2)=-(2x - 3)-2\), but a simpler way is to note that \(5 - 2x=-(2x - 5)=-(2x-3 + 2)\) is not necessary. Instead, we can factor out a negative sign from the second denominator: \(5 - 2x=-(2x - 5)=-(2x-3 + 2)\) is incorrect. The correct way is \(5 - 2x=-(2x - 5)=-(2x-3 - 2)\) no, better: \(5 - 2x=-(2x - 5)=-(2x-3 - 2)\) is wrong. Let's do it as \(5 - 2x=-(2x - 5)=-(2x-3 - 2)\) no. The correct approach is:
\(\frac{1}{2x - 3}+\frac{1}{5 - 2x}=\frac{1}{2x - 3}-\frac{1}{2x - 5}\) (since \(\frac{1}{5 - 2x}=\frac{1}{-(2x - 5)}=-\frac{1}{2x - 5}\))

Step 2: Find a common denominator

The common denominator of \(2x - 3\) and \(2x - 5\) is \((2x - 3)(2x - 5)\)

$$ \frac{1}{2x - 3}-\frac{1}{2x - 5}=\frac{(2x - 5)-(2x - 3)}{(2x - 3)(2x - 5)} $$

Step 3: Simplify the numerator

Simplify the numerator: \((2x - 5)-(2x - 3)=2x-5 - 2x + 3=-2\)
So the expression simplifies to \(\frac{-2}{(2x - 3)(2x - 5)}=\frac{2}{(3 - 2x)(2x - 5)}\) (we can also multiply the denominator out: \((2x - 3)(2x - 5)=4x^{2}-10x-6x + 15=4x^{2}-16x + 15\), so \(\frac{-2}{4x^{2}-16x + 15}\))

Answer:

\(x =-\frac{19}{5}\)

Problem 2: Solve \(\boldsymbol{\frac{1}{x - 3}=6}\)