Respuesta :

MsRay

Answer:

Equation:  [tex]\frac{1}{2}[/tex]n - 7 = 3n - 33

Answer:  n = 10.4

Step-by-step explanation:

Using key words from the verbal description, you can set up an equation to solve for the missing variable.  Start with one part of the description at a time:  '7 less than half a number'.  Half a number = [tex]\frac{n}{2}[/tex] or [tex]\frac{1}{2}[/tex]n.  '7 less than' means we have to subtract 7 from that number:   [tex]\frac{1}{2}[/tex]n - y.  'Is equal' is our  '=' sign.  Next, 33 less than three times the number.  'Three times a number' = 3n. '33 less than' means we have to subtract 33 from 3n:  3n - 33.  Put them together:

[tex]\frac{1}{2}[/tex]n - 7 = 3n - 33

Use inverse operations to solve by adding 33 to both sides:

[tex]\frac{1}{2}[/tex]n - 7 + 33 = 3n - 33 + 33 or [tex]\frac{1}{2}[/tex]n + 26 = 3n

Use inverse operations to subtract [tex]\frac{1}{2}[/tex]n from both sides:

[tex]\frac{1}{2}[/tex]n + 26 - [tex]\frac{1}{2}[/tex]n  = 3n - [tex]\frac{1}{2}[/tex]n

Combine like terms:  26 = 2.5n, then divide both sides by 2.5: 26/2.5 = 2.5n/2.5.

n = 10.4