help is needed!!! please

Answer:
5
Step-by-step explanation:
There are 2 ways to look at this. I will explain both.
First we have the 3-4-5 triangle method, stating that any triangle with sides 3 and 4 will have the last side as 5.
Now, for the more complex way of doing this, we can use the Pythagorean theorem to solve this problem.
Pythagorean theorem: [tex]a^2+b^2=c^2[/tex]
We can use 4 for a and 3 for b
You will now have
[tex]4^2+3^2=c^2\\\\16+9=c^2\\25=c^2[/tex]
Then take √25, or 5.