Why are 2.15 and -2.15 opposites explain

Aparallelogram has an area of 216.24 cm2 and a height of 15.9 cm. how long is the base of the parallelogram? enter your answer as a decimal in the box. cm

The triangles are similar. what is the value of x? show your work.

Avery’s piggy bank has 300 nickels, 450 pennies, and 150 dimes. she randomly picks three coins. each time she picks a coin, she makes a note of it and puts it back into the piggy bank before picking the next coin.