Respuesta :

1. Answer:   [tex]y=\dfrac{3}{4}x-3[/tex]    [tex]m=\dfrac{3}{4}[/tex]     [tex]b=-3[/tex]

Step-by-step explanation:

The slope-Intercept form is: y = mx + b

  • m is the slope
  • b is the y-intercept

3x - 4y = 12

     -4y = -3x + 12    subtracted 3x from both sides

       [tex]\dfrac{-4}{-4}y=\dfrac{-3}{-4}x+\dfrac{12}{-4}[/tex]    divided both sides by -4

        [tex]y=\dfrac{3}{4}x-3[/tex]

  • m = [tex]\dfrac{3}{4}[/tex]
  • b = -3

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2. Answer:   [tex]y=\dfrac{1}{3}x-5[/tex]    [tex]m=\dfrac{1}{3}[/tex]     [tex]b=-5[/tex]

Step-by-step explanation:

The slope-Intercept form is: y = mx + b

  • m is the slope
  • b is the y-intercept

x - 3y = 15        

    -3y = -x + 15    subtracted x from both sides

       [tex]\dfrac{-3}{-3}y=\dfrac{-1}{-3}x+\dfrac{15}{-3}[/tex]    divided both sides by -3

        [tex]y=\dfrac{1}{3}x-5[/tex]

  • m = [tex]\dfrac{1}{3}[/tex]
  • b = -5

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3. Answer:   y = -5x + 9    m = -5     b = 9

Step-by-step explanation:

The slope-Intercept form is: y = mx + b

  • m is the slope
  • b is the y-intercept

5x + 2y = y + 9

5x + y = 9       subtracted y from both sides

        y = -5x + 9    subtracted x from both sides

  • m = -5
  • b = 9

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4. Answer:   [tex]x=-\dfrac{5}{7}[/tex]    [tex]x=3[/tex]    

Step-by-step explanation:

To solve an absolute value equation:

  • isolate the absolute value expression
  • split the equation into 2 equations (one positive and one negative)
  • solve for each equation
  • NOTE: absolute value expression cannot be equal to a negative

| 7x - 8 | = 13     isolated absolute value expression is equal to a positive

-(7x - 8) = 13          +(7x - 8) = 13    separated into 2 equations

 7x - 8  = -13            7x - 8 = 13     divided by the +/- sign

  7x      = -5             7x       = 21     added 8 to both sides

    x      = [tex]-\dfrac{5}{7}[/tex]               x       = 3      divided both sides by 7

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5. Answer:   x = -9   x = -2

Step-by-step explanation:

To solve an absolute value equation:

  • isolate the absolute value expression
  • split the equation into 2 equations (one positive and one negative)
  • solve for each equation
  • NOTE: absolute value expression cannot be equal to a negative

3| 2x + 11 | = 21     need to divide both sides by 3

 | 2x + 11 | = 7    isolated absolute value expression is equal to a positive

-(2x + 11) = 7          +(2x + 11) = 7    separated into 2 equations

 2x + 11 = -7            2x + 11 = 7     divided by the +/- sign

  2x      = -18             2x      = -4     subtracted 11 from both sides

    x      = -9               x       = -2      divided both sides by 2

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6. Answer:   No solution

Step-by-step explanation:

To solve an absolute value equation:

  • isolate the absolute value expression
  • split the equation into 2 equations (one positive and one negative)
  • solve for each equation
  • NOTE: absolute value expression cannot be equal to a negative

-2| x + 7 | - 3 = 13     need to add 3 to both sides

-2| x + 7 |      = 16     need to divide both sides by -2

| x + 7 |  = -8    isolated absolute value expression is equal to a negative

It is not possible for a positive (absolute value) to be equal to a negative so there is no solution.