IXL AA.3 7th grade! (click photo)

Which best explains why this triangle is or is not a right triangle?

Which expressions are equivalent to -7+3(-4e-3)? choose all answers that apply: choose all answers that apply: a -4(3e+4)? 4(3e+4) b 12e12e c none of the above

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?