Answer:
x = 27
Step-by-step explanation:
ΔBRD and ΔQCD are similar, hence the ratios of corresponding sides are equal, that is
[tex]\frac{BD}{QD}[/tex] = [tex]\frac{RD}{CD}[/tex]
note that BD = 26 + 39 = 65
substitute values into the ratio equation
[tex]\frac{65}{39}[/tex] = [tex]\frac{x+18}{x}[/tex] ( cross- multiply )
65x = 39(x + 18)
65x = 39x + 702 ( subtract 39x from both sides )
26x = 702 ( divide both sides by 26 )
x = 27
