Helen has some pens and some square tiles .each pen is 130mm longet . the sides of each tile are 13mm long . helen lays ten pens end to end to make a straight line . she makes a line of tiles which is the same length as the line of pens . how many tiles does she use?

Is there a direction u in which the rate of change of f(x,y)equals=x squared minus 3 xy plus 4 y squaredx2−3xy+4y2 at p(1,2) equals 14? give reasons for your answer. choose the correct answer below. a. no. the given rate of change is smaller than the minimum rate of change. b. no. the given rate of change is larger than the maximum rate of change. c. yes. the given rate of change is larger than the minimum rate of change and smaller than the maximum rate of change.