Answer:
u should put this also in English then type it in so it will translate
We have been given an expression
. We are asked to factor the given expression by grouping.
First of all, we will make two groups of our expression as:

Now we will factor of greatest common factor from each group.


Now we will factor out common terms
as:

Therefore, the factorized form of our given expression would be
.
40. m∠2=148° m∠4=148°
41. ∠2 and ∠5
42. ∠1 and ∠2
43. ∠3 and ∠5
Sorry, I don't know how to do the rest, but I hope this helps!
Answer:
To check if a given value is a solution to an equation:
Evaluate the left-hand side expression at the given value to get a number.
Evaluate the right-hand side expression at the given value to get a number.
See if the numbers match.
15x=180
x=12
hope this helps