Respuesta :

it should be :
1/3(x + 18) = 7
1/3x + 6 = 7
1/3x + 6 - 6 = 7 - 6
1/3x = 1
x = 3

Answer:

(B)

Step-by-step explanation:

The given expression is:

[tex]\frac{1}{3}(x+18)=7[/tex]

Upon solving the above expression, we get

[tex]\frac{1}{3}(x+18)=7[/tex]

Step 1. Solving the above equation, we get

[tex]\frac{1}{3}x+6=7[/tex]

Step 2. Subtracting 6 on both the sides of the above equation, we have

[tex]\frac{1}{3}x+6-6=7-6[/tex]

Step 3. The equation can be written as:

[tex]\frac{1}{3}x=1[/tex]

Step 4. Cross multiplying the above equation , we have

[tex]x=3[/tex]

She made an error in step 2 as she added 6 on right hand side but in actual we have to subtract 6 on that side.

Thus, option (B) is correct.