To approximate the number of visitors in 1985 using the equation \( y = 1.38x + 3.26 \), we first need to determine the value of \( x \) corresponding to the year 1985.
Since \( x = 0 \) represents the year 1970, we can calculate \( x \) for 1985 as follows:
\[ x = 1985 - 1970 = 15 \]
Now, we substitute \( x = 15 \) into the equation:
\[ y = 1.38(15) + 3.26 \]
Calculating \( 1.38 \times 15 \):
\[ 1.38 \times 15 = 20.7 \]
Now adding 3.26:
\[ y = 20.7 + 3.26 = 23.96 \]
Since \( y \) is in thousands, the approximate number of visitors in 1985 is:
\[ y \approx 23.96 \times 1000 = 23960 \]
Thus, the approximate number of visitors to the museum in 1985 is 23,960.