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finding missing angles
Work out what you need to know
Based on your sketch, you need to work out what your theory actually
means in terms of points, lines, and angles.
In this case we’ve got a few important details. We have a line from the
point where Charlie was standing, through the hole in the window, until
it hits the parked car. We also sketched a line moving backward from the
bullet, until that hits the parked car, too.
If our theory is true, and Charlie was the shooter, the way the bullet
bounced off the car is important.
You guys have a bouncing bullet? Cool! Well,
whenever we do lab tests on this type of
bullet they always bounce out at the same
angle as they bounced in on. Does that help?
If our bullet bounced as the lab technician
described, what do we know should be
true about mystery angles x and y?
TIRE
TRACKS
x and y are supplementary
x is less than y
x is equal to y
nothing—they could be any angles
xº
yº
The bullet bounced equally
like this…
…not like this.
bounce
bounce
It’s always worth making
sure the lab technicians
have enough coffee.
Handy lab guy