Need help! Thank you :)

Answer:
The value of [tex]x[/tex] is 10.
Step-by-step explanation:
Both angles ABC and CBD are complementary, that is, the sum of the measures of both angles equals 90°, that is:
[tex]\angle ABC + \angle CBD = 90^{\circ}[/tex] (1)
If we know that [tex]\angle ABC = 5\cdot x[/tex] and [tex]\angle CBD = 4\cdot x[/tex], then the value of [tex]x[/tex] is:
[tex]5\cdot x + 4\cdot x = 90^{\circ}[/tex]
[tex]9\cdot x = 90^{\circ}[/tex]
[tex]x = 10[/tex]
The value of [tex]x[/tex] is 10.