are these declensions right? thanks for checking them.

bonus rex
bonis regis
boni regi
bonem regem
bone rege

reges bones (macrons on e's)
regum bonum
regibus bonibus
reges bones (macrons)
regibus bonibus

mater meu
Matris meuis
matri meui
matrem meum
matre meue
matres meues
matrem meuem
matribus meuibus
matres meues
matribus meuibus

3 answers

Where are you getting these adjectives from?

The nouns look OK:
(3rd declension)
rex
regis
regi
regem
rege

reges
regum
regibus
reges
regibus

(also 3rd declension)
mater
matris
matri
matrem
matre

matres
matrum
matribus
matres
matribus

But those adjectives!! Holy smoke!! You need to make them match the nouns (which are in 3rd declension) and yet stay in their own declensions. Bonus, a, um and meus, a, um are first and second declensions.

What are the endings for first declension? They will be needed for me- to modify mater.

What are the endings for second declension? They will be needed for bon- to modify rex.

So ... the nouns are fine. Just fix the adjectives. Repost whenever you're ready.
3rd declension noun with 2nd declension adjective
rex bonus
regis boni
regi bono
regem bonum
rege bono

reges boni (macrons on e's)
regum bonorum
regibus bonis
reges bones (macrons)
regibus bonis

3rd declension noun with 1st declension adjective
mater mea
matris meae
matri meae
matrem meam
matre mea

matres meae
matrum mearum
matribus meuis
matres meas
matribus meis

(With macrons in the correct places.)

See the explanation at the top of this webpage and the charts at the bottom:
http://www.everything2.com/title/Latin%2520noun%2520declensions
matribus meuis <~~incorrect

matribus meis <~~corrected