x=225.5 or x=134.5
If we let xxx be the distance of a point from the right end of the wall, then:
|x-180|∣x−180∣vertical bar, x, minus, 180, vertical bar
is the distance from the point to the center of the wall. If the poster is centered, then:
2|x-180|2∣x−180∣2, vertical bar, x, minus, 180, vertical bar
represents the width of the poster.
Hint #2
Since the poster is 91\,\text{cm}91cm91, start text, c, m, end text wide, we have:
\begin{aligned} 2|x-180|=&91 \\\\ |x-180|=&45.5 \end{aligned}
2∣x−180∣=
∣x−180∣=
91
45.5
So either:
x-180=45.5x−180=45.5x, minus, 180, equals, 45, point, 5
or
x-180=-45.5x−180=−45.5x, minus, 180, equals, minus, 45, point, 5
Therefore:
x=225.5\,\text{cm}x=225.5cmx, equals, 225, point, 5, start text, c, m, end text or x=134.5\,\text{cm}x=134.5cmx, equals, 134, point, 5, start text, c, m, end text
Hint #3
The left edge of the poster is 225.5\,\text{cm}225.5cm225, point, 5, start text, c, m, end text from the right end of the wall and the right edge of the poster is 134.5\,\text{cm}134.5cm134, point, 5, start text, c, m, end text from the right end of the wall.