It has to be 12. I mulitplied 8 x 1.5
Answer:
3) 16.2
Step-by-step explanation:
The supplement to the 115° angle on the right is 65°, the same as the angle at upper left. The vertical angles at C are the same measure, so this tells you that the two triangles FCB and ACD are similar by the AA similarity postulate. That being the case, corresponding sides are proportional:
CB/CD = CF/CA
CB = CD·CF/CA = 7.2·21.6/9.6
CB = 16.2
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When given two "point-to-point" triangles like this, quite often there is some sort of similarity relationship involved. First, you need to figure out what it is; then you need to make use of it as needed to answer the question being asked.
4/6 = x + 3/ 12 - x
4( 12 - x) = 6( x + 3)
48 - 4x = 6x + 18
-4x - 6x = 18 - 48
- 10x = -30
x = 3
