Answer:

Step-by-step explanation:

A system of linear equations is a set of two linear equations with two variables.
Answer:

Step-by-step explanation:
Given



Required
Determine CD
Since, C is a point on BD, the relationship between the given parameters is;

Substitute the values of BD, BC and CD

Collect Like Terms


Divide both sides by -4


To determine the length of CD;
Substitute 3 for x in 
Hence;

1. -4 times 3 and 21
2.add -12 and -84
3.-96 dived by 2
4 equals -48