John found that the perimeter of a square is 2x+30 ft. If the perimeter's length is 128

ft 128 ft what is the value of x?
x=____ft

1 answer

The perimeter \( P \) of a square can be calculated using the formula:

\[ P = 4s \]

where \( s \) is the length of one side of the square. According to the problem, John found that the perimeter can also be expressed as \( P = 2x + 30 \) ft. We are given that the perimeter is also equal to 128 ft.

To find the value of \( x \), we can set the two expressions for the perimeter equal to each other:

\[ 2x + 30 = 128 \]

Now, we will solve for \( x \):

  1. Subtract 30 from both sides:

\[ 2x = 128 - 30 \] \[ 2x = 98 \]

  1. Now, divide both sides by 2:

\[ x = \frac{98}{2} \] \[ x = 49 \]

Thus, the value of \( x \) is

\[ \boxed{49 \text{ ft}} \]