ok let's do this*pops knuckles*
let's add the first side

order of operations demands that we do multiplication first(P.E.M.D.A.S)
so

now we can add the 1 from

into our six

now we substract

now we have

now we focus on the
other side

since 5 is in paranthesis we use something called the distributive property. it mean we will multiply the 5 by both of the 2.

now we have

(the three is from the original equation)
now we plug in our final numbers

or

I hope this helps