SAT Math 5.5 Geometry and Measurement

SAT Math 5.5 Geometry and Measurement

GeometryTriangles
LanguageEnglish Language
MathGeometry
Problem Solving and Data AnalysisKey features of graphs
Product TypeSAT Math
SAT MathGeometry and Measurement
TrianglesSimilar Triangles

Transcript

00:25

Now how do we find FE and EG?

00:29

What do we know about similar triangles?

00:32

All corresponding angles are equal from one to the next…okay, good to know…

00:36

…and the other thing is that all corresponding sides have a relative length.

00:40

In other words, if the length of one side is doubled, then the lengths of all sides are doubled.

00:48

Triangle ABC isn’t going to help us much at the moment…

00:51

…because although two of its sides are labeled, it’s missing the one that we do have for triangle EFG.

00:57

Whereas, with triangle EDC, the side that is labeled as “3” directly corresponds to side FG.

01:04

So now we know that everything in triangle EDC is triple that of triangle EFG.

01:09

We also know that line CE is 2.25…so if the corresponding side in triangle EFG, side

01:16

EG, is one-third of that length… it must be 0.75 units in length.

01:22

All right…now we can see the relationship between triangles EFG and ABC.

01:27

Looks like ABC is twice as large as its counterpart to the right.

01:32

In that case, since line AB is “2,” line EF must be “1.”

01:38

And now it’s just a case of adding ‘em up… 1 plus 1 plus 0.75 = 2.75…

01:45

…answer A.