Final answer:
To find the value of x.m(9x+18)(2X+19) given l || m || n, simplify the expression by expanding and solving.
Step-by-step explanation:
Given l || m || n, the value of x.m(9x+18)(2X+19) can be determined as follows:
Since l || m || n, it means that the lines are parallel.
This implies that x and m are corresponding angles and they are congruent.
Therefore, we can simplify the expression: x.m(9x+18)(2X+19) = x²(9x+18)(2x+19).
From here, you can simplify further by expanding and solving the expression.