The issue is that calculus in itself with symbolic algebra is next to useless for average person. However intuitive concepts, like area under a curve, are not.
I "solve for x" all the time, though, admittedly, outside of work, it rarely gets more complicated than a simple expression with a fraction or two.
However, what is aggressively useful is dimensional analysis. When I'm doing a calculation and need to quickly check that the formulation is right, checking the units works every time.
However, what is aggressively useful is dimensional analysis. When I'm doing a calculation and need to quickly check that the formulation is right, checking the units works every time.