We can see that together, 13x° and 5y° make a right angle (they are called complementary angles).
[tex]13x+5y=90[/tex]
We also see that 155° and 5y° make a straight angle, or a 180°-angle (they are called supplementary angles).
[tex]5y+155=180[/tex]
Let's first solve for y.
[tex]5y=180-155\\y=5[/tex]
Let's plug in our value of y and solve for x.
[tex]13x+5(5)=90\\13x=65\\x=5[/tex]