Answer:
[tex]CD = 3[/tex]
Step-by-step explanation:
Given
[tex]CD = x[/tex]
[tex]BC = 5x - 5[/tex]
[tex]BD = 2x + 7[/tex]
Required
Determine CD
Since, C is a point on BD, the relationship between the given parameters is;
[tex]BD = BC + CD[/tex]
Substitute the values of BD, BC and CD
[tex]2x + 7 = 5x - 5 + x[/tex]
Collect Like Terms
[tex]2x - 5x - x = -5 - 7[/tex]
[tex]-4x = -12[/tex]
Divide both sides by -4
[tex]\frac{-4x}{-4} = \frac{-12}{-4}[/tex]
[tex]x = 3[/tex]
To determine the length of CD;
Substitute 3 for x in [tex]CD = x[/tex]
Hence;
[tex]CD = 3[/tex]