$\mathrm{♣}\cdot \mathrm{♣}=9\backslash clubsuit\backslash cdot\; \backslash clubsuit=9$

$\mathrm{♣}=3\backslash clubsuit=3$

$\mathrm{♣}+\mathrm{♡}=13\backslash clubsuit+\backslash heartsuit=13$

$\mathrm{♡}=13-3\backslash heartsuit=13-3$

$\mathrm{♡}=10\backslash heartsuit=10$

$\mathrm{♢}\cdot \mathrm{♣}+\mathrm{♡}=28\backslash diamondsuit\backslash cdot\; \backslash clubsuit+\backslash heartsuit=28$

$\mathrm{♢}=(28-10):3\backslash diamondsuit=(28-10):3$

$\mathrm{♢}=6\backslash diamondsuit=6$

$\mathrm{♣}\cdot \mathrm{♡}-\mathrm{♢}=\backslash clubsuit\backslash cdot\; \backslash heartsuit-\backslash diamondsuit=$$3\cdot 10-63\backslash cdot\; 10-6$

$\mathrm{♣}\cdot \mathrm{♡}-\mathrm{♢}=24\backslash clubsuit\backslash cdot\; \backslash heartsuit-\backslash diamondsuit=24$