Afactory requires 84 machines to produce a given number of articles in 32 days. how many machines would be required to produce the same number of articles in 21 days?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

He ! a group of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?

What is the value of the discrimination for the quadratic equation 0=×2+2+×2