1 + 1/5 + 3.75 - (-x) = 4.5

Convert 1 + 1/5 to an improper fraction:

1 + 1/5 = 5/5 + 1/5 = 6/5

Substitute this back into the equation:

6/5 + 3.75 - (-x) = 4.5

Combine the fractions:

6/5 + 3.75 - (-x) = 4.5

Convert 3.75 to a fraction:

3.75 = 3 75/100 = 3 3/4 = 15/4

Now, the equation becomes:

6/5 + 15/4 + x = 9/2

To simplify, find a common denominator for 5 and 4, which is 20:

24/20 + 75/20 + x = 90/20

Combine the fractions:

99/20 + x = 90/20

Now, solve for x:

x = 90/20 - 99/20
x = -9/20

Therefore, the value of x in the equation is -9/20.