What is the angle addition postulate?

Agroup of three friends order a combo meal which includes two slices of pizza and a drink each drink is priced at $2.50 the combined total of $31.50 how much is the cost of a slice of pizza

Jaxon has s packs of 8 crazy straws. he divided the crazy straws into 2 equal bags. now, he has 224 crazy straws in each bag. how many packs of crazy straws did jaxon start with?

Find two numbers if their ratio is 4: 7 and their difference is 123.