How did the fifteen amendment expand on the rights granted in the thirteenth and fourteenth amendments?

The 13th Amendment outlawed slavery

The 14th Amendment stated that no state shall abridge the rights of any citizens

The 15th Amendment, ostensibly, gives the right to vote to African-American men. It states that "The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of race, color, or previous condition of servitude."

So, the 15th Amendment worked to codify, or bring into fruition, a whole new group of voting citizens who had equal protection under the law in a system where slavery is now illegal.

The amendment reconstruction is grouped into the 13th to 15th amendments in the American laws. At the last amendment of the constitution, the amendments were essential and implemented the construction of the southern war.

The thirteenth amendment proposal aimed at abolishing slavery as well as the involuntary servitude.

The 14th amendment of the contrary addressed the rights of the citizens and advocated for the protection of all people by the law.

Moreover, the 15th amendment prohibited discrimination and fought for people voting rights.