3h^2+8h+5 how do you work it?

Do you mean, solve: 3h² + 8h + 5 = 0 ?

Use the quadratic formula:

$$h = \frac{-b +/- sqrt(b^{2}-4ac)}{2a}$$

We get:

$$h = \frac{-8 +/- sqrt(8*8 - 4*3*5)}{2*3}$$

$$h= \frac{-8 +/- sqrt(64-60)}{6}$$

$$h = \frac{-8 +/- 2}{6} => h= \frac{-10}{6} ...v... h=\frac{-6}{6}$$

h = - 5/3  v  h = -1 

Where v is latin for "vel", indicating inclusive disjunction:

A v B means "A or B", or more precise: "either A, or B, or both"

Excellent presentation Tetration