similar triangle triples

if the width of the rectangle is 15cm and the length is 20cm

what are the lengths a , b , and c?








you can work out the lengths a, b and c without using pythagoras

because the triangles are similar: a = 4k, b = 3k and so c = 9/4k
then use areas of triangles (knowing the area of the rectangle) to find these lengths

three similar right angled triangles make up a rectangle

what are the lengths of their sides?

again,
you do need to use pythagoras