On Christmas, a shopkeeper needs 820 candles. If each packet contains 20 candles, how many packets he should buy?

Step-by-step explanation:

if the shopkeeper needs 820 candles,

each packet has 20 candles

820/20=41

he needs to buy 41 packets  

b) k’(6, 4); l’(3, 3)

step-by-step explanation:

a 270° clockwise rotation maps every point (x, y) to (y, -x). (it negates the x-coordinate and then switches it and the y-coordinate.)

this means the endpoints of the side congruent to kl, k' and l', would be mapped as:

k'(-4, 6)→(6, 4)

l'(-3, 3)→(3, 3)