So one way we can do this is-
2(2n+7)+3n=
4n+14+3n=
7n+14
Another simpler way possible is-
2n+7+2n+7+3n=
RE-ORDER
2n+2n+3n+7+7=
COMBINE LIKE TERMS
7n+14
Well.. .not exactly what you're asking, but the relationship of them is

so... hmm to add some
for example let's say
The problem deals with a division and the rest of it, that is dividing the total amount of pencils into 9 classrooms and the rest, lets express it as fraction:
935/9 = 103 + 8/9
that is, if we multiply 103*9 we get 927 and are 8 pencils left over, therefore, 8 pencils are donated to the library and each classroom gets 103 pencils, in total 935 pencils are donated.
Answer:
Y = 170, Z = 64.
Step-by-step explanation:
Since y is the external angle to x, which you got right, it is in fact, 180-10, = 170 degrees. And since z is the external to our unknown angle, that means it is equal to the sum of the other two angles in the triangle. That means z is 54 + 10, which is 64.