Answer:
Step-by-step explanation:
We can use Hypotenuse Theorem for this:
For triangle ABC,
AC²=CB²+BA²
9²=CB²+3²
Switch the sides
-CB²=3² -9²
-CB²= 9-81
-CB²= -72
the signs cut each other
CB²=72
the square changes sides
CB=√72
CB= 8.49 cm
Now triangle CBD
We have the length of CB but not the other two whereas we have the angle
It will be sin
As we know sin= O/H
Here O is CB whereas H is CD
Put the values
sin 50= 8.49/H
H= 8.49 ÷sin 50
Calculate
H=11.1 cm
As we know H is CD so CD is 11.1 cm
Hope it helps