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SAT Math 1.1 Algebra and Functions. Find an algebraic equation to correspond with the data.
SAT Math 1.1 Geometry and Measurement. What is the circumference of the circle?
SAT Math 1.1 Numbers and Operations. How many combinations of beverage and cereal can be made?
SAT Math 5.2 Geometry and Measurement 253 Views
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Description:
SAT Math 5.2 Geometry and Measurement
Transcript
- 00:02
Here’s your shmoop du jour, brought to you by interlocking circles.
- 00:13
How many tangent lines can be drawn to exactly two circles in the picture below?
- 00:18
Here are the potential answers...
- 00:22
First up, let’s make sure we all know what a tangent is.
- 00:26
And no, it's not a funky kind of orange.
Full Transcript
- 00:28
The one that connects at an arc or circle at exactly one point is a tangent.
- 00:38
The easiest way to solve this problem is to start by imagining that one of these circles isn’t even there.
- 00:45
Poof, it’s gone.
- 00:46
There are all sorts of tangent lines we can draw to one of these circles…
- 00:49
…but only two will hit both circles at exactly one point.
- 00:54
Now if we do the same with a different pair of circles, we get the same result.
- 00:59
Same deal with the final pair.
- 01:01
So…looks like we get 2 tangents times 3 possible pairings…
- 01:05
…for a grand total of 6 tangent lines.
- 01:07
And boom, we’ve got our answer – option D.
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