Secant DB intersects secant DZ at point D. Find the length of DA

Answer:
The length of DA is 3 units.
Step-by-step explanation:
Given information: YZ=32, DY=x, DA=3x adn AB=8.
By using intersection secant theorem:
[tex]DY\times DZ=DA\times DB[/tex]
[tex]DY\times (DY+YZ)=DA\times (DA+AB)[/tex]
[tex]x\times (x+32)=3x\times (3x+8)[/tex]
[tex]x^2+32x=9x^2+24x[/tex]
[tex]9x^2+24x-x^2-32x=0[/tex]
[tex]8x^2-8x=0[/tex]
[tex]8x(x-1)=0[/tex]
[tex]x=0,x=1[/tex]
The value of x can not be zero, therefore the value of x is 1 and the length of DA is
[tex]3x=3\times 1=3[/tex]
Therefore the length of DA is 3 units.