What does "m" represent in y=mx+b

Which expression gives you the distance between the points (5,1)and(9,-6)

Abarbecue sold 26 hamburgers and hot dogs. hamburgers sell for $3.50 each and hot dogs sell for $2.00 each. if the barbecue made $70 in sales, determine and state the number of hot dogs sold.

In the triangles, bc =de and ac fe.if the mzc is greater than the mze, then ab isdfelth