Which 9th-century Persian mathematician is often referred to as the "father of algebra" for his work 'The Compendious Book on Calculation by Completion and Balancing'?

Al-Khwarizmi

The word 'algebra' comes from the Arabic 'al-jabr,' which means 'the restoration of broken parts.' Al-Khwarizmi's work was so influential that his name is also the root for the word 'algorithm.'