Algebra 2 will mark brainliest. 4 pictures 4 questions

Offering 30 if a plus b plus c equals 68 and ab plus bc plus ca equals 1121, where a, b, and c are all prime numbers, find the value of abc. the answer is 1978 but i need an explanation on how to get that.

Which coefficient matrix represents a system of linear equations that has a unique solution ? options in photo*

What’s -11-33k and factor each expression completely