Question: State if the triangles in each pair are similar. If so, state how you know they are similar and complete the similarity statement.
△BCD ~ ______
A) similar; AA similarity; △KLB
B) similar; SAS similarity; △BKL
C) not similar
D) similar; SSS similarity; △KLB
Graph/shapes: A large triangle with vertices C at left, D at upper right, and B at lower right; point K lies on segment CB near the middle, and point L lies on segment DB. A smaller triangle KLB is drawn inside the large triangle. The base CB is labeled 4, segment KB is labeled 1, and side DB is labeled 2 with a blue double-arrow measurement. position_hint: center
1. **State the problem:** Determine if triangles △BCD and △KLB are similar, and if so, identify the similarity criterion and complete the similarity statement.
2. **Given information:**
- Triangle △BCD with vertices B, C, D.
- Smaller triangle △KLB inside △BCD.
- Segment CB = 4 units.
- Segment KB = 1 unit.
- Segment DB = 2 units.
3. **Analyze side lengths:**
- Since KB = 1 and CB = 4, then CK = CB - KB = 4 - 1 = 3 units.
- Side DB = 2 units.
4. **Check ratios of corresponding sides:**
- Compare sides in △BCD and △KLB.
- Side CB in △BCD corresponds to KL in △KLB.
- Side DB in △BCD corresponds to LB in △KLB.
5. **Calculate ratios:**
- Ratio of KB to CB is $\frac{1}{4}$.
- Ratio of DB to LB is given as 2 to ? (LB length not given explicitly).
6. **Use similarity criteria:**
- Since the smaller triangle is inside the larger one and points K and L lie on sides CB and DB respectively, triangles share angle at B.
- If two sides are proportional and the included angle is equal, SAS similarity applies.
7. **Conclusion:**
- Triangles △BCD and △KLB are similar by SAS similarity.
- The similarity statement is $\triangle BCD \sim \triangle KLB$.
**Final answer:**
Option B) similar; SAS similarity; $\triangle BKL$ (Note: The problem states $\triangle BKL$ in option B, but the smaller triangle is $\triangle KLB$, which is the same triangle with vertices reordered. So the similarity statement is $\triangle BCD \sim \triangle KLB$.