Chapter: Geometric Constructions· Mathematics Part 2 (Geometry)
Answer: \(\Delta XLM\) has XL = 3.6 cm, LM = 4.2 cm, XM = 3.15 cm.
Analysis: \(\dfrac{XY}{XL} = \dfrac{YZ}{LM} = \dfrac{XZ}{XM} = \dfrac{4}{3}\). \(XL = \dfrac{3 \times 4.8}{4} = 3.6\) cm, \(LM = \dfrac{3 \times 5.6}{4} = 4.2\) cm, \(XM = \dfrac{3 \times 4.2}{4} = 3.15\) cm. The two triangles share vertex X.
Steps of construction:
- Draw seg XY = 4.8 cm. With X as centre radius 4.2 cm and Y as centre radius 5.6 cm draw arcs meeting at Z. Join XZ and YZ.
- Draw ray XT making an acute angle with XY on the side opposite Z; mark 4 equal parts \(X_1, X_2, X_3, X_4\).
- Join \(X_4Y\). Through \(X_3\) draw a line parallel to \(X_4Y\), meeting XY at L.
- Through L draw a line parallel to YZ, meeting XZ at M. \(\Delta XLM\) is the required triangle.
The ray method avoids measuring 3.15 cm. Check: XL ≈ 3.6 cm and LM ≈ 4.2 cm.
[Figure: \(\Delta XYZ\) with the smaller \(\Delta XLM\) inside it at vertex X, LM parallel to YZ.]