Answer:
Let do this..
Step-by-step explanation:
ABCD is a parallelogram - 1
In ∆ADC and ∆CBA
AC=AC (Common)
<DAC=<BCA (Given)
AD=CB (From 1)
Therefore, ∆ADC = ∆CBA (By SAS)
3(z+3) = 3z + 9 if thats what your asking
Regards!
I hope it helps you :)