HP 39gs User Manual page 93

Solve aplet
5. Move the cursor near the positive (right-side)
intersection. This cursor value will be an initial guess
for T.
Press until the
cursor is at the
intersection.
The two points of
intersection show that
there are two solutions for this equation. However,
only positive values for X make sense, so we want to
find the solution for the intersection on the right side
of the y-axis.
6. Return to the Numeric
view.
Note: the T-value is filled in with the position of the
cursor from the Plot view.
7. Ensure that the T value is highlighted, and solve the
equation.
Use this equation to solve for another variable, such as
velocity. How fast must a body's initial velocity be in
order for it to travel 50 m within 3 seconds? Assume the
same acceleration, 4 m/s
the initial guess.
3
50
2
. Leave the last value of V as
7-9