How old are the oldest parts of the Cascade mountains to be made of
volcanoes?

About two million years ago eruptions began construction of the ancestral cones in the vicinity of the present Cascade volcanoes. Mount Rainier's current volcanic cone began building around 500,000 years ago.

would be false hope this out

pythagoras' theorem

square root (-5^2+9^2)

square root (25+81)

square root (106)

angle is tan^-1(9/5)

neg x, pos y