Simplify 3(3+8)square + (1square+5square)=

Use PEMDAS:
P Parentheses first
E Exponents (ie Powers and Square Roots, etc.)
MD Multiplication and Division (left-to-right)
AS Addition and Subtraction (left-to-right)
[tex]3(3+8)^2+(1^2+5^2)=3(11)^2+(1+25)=3(121)+26=363+26=389[/tex]