Answer:
x=8
this is because you do 57+89=146
and then you do 180-146 because a triangle adds up to 180.
this gives you 34
so the value of 5x-6=34
add the 6 onto 34 which gets rid of the -6 ans fives you the answer of 40
After that yoy divide 40 by 5 which gives you the value of x which is 8
