Answer:6√3
Step-by-step explanation:Before we begin, remember the following:
Now, for the given:75 can be written as 25*3
This means that:

Applying the above concept, we can find that:

Now, we know that:
√25 = 5 (we ignored the negative value)
This means that:
√75 = 5√3
Finally, we can compute the needed sum as follows:
√75 + √3 = 5√3 + √3 = 6√3
Hope this helps :)