Answer:
[tex]x=27\ units[/tex]
Step-by-step explanation:
we know that
Triangles BDR and QDC are similar, because QC and BR are parallel lines
If two figures are similar, then the ratio of its corresponding sides is equal and is called the scale factor
In this problem
[tex]\frac{QD}{BD} =\frac{DC}{RD}[/tex]
substitute the values
[tex]\frac{39}{39+26} =\frac{x}{x+18}[/tex]
[tex]\frac{39}{65} =\frac{x}{x+18}[/tex]
[tex]65x=39(x+18)[/tex]
[tex]65x-39x=702[/tex]
[tex]26x=702[/tex]
[tex]x=702/26[/tex]
[tex]x=27\ units[/tex]
