Match the following columns:
Column I | Column II |
A. In a given ΔABC, DE || BC and | P. 6 |
B. If ΔABC ~ ΔDEF such that 2AB = 3DE and BC = 6 cm then EF = ……….. cm. | Q. 4 |
C. If ΔABC ~ ΔPQR such that ar(ΔABC) : ar(ΔPQR) = 9 :16 and BC = 4.5 cm then QR = cm. | R. 3 |
D. In the given figure, AB || CD and OA = (2x + 4) cm, OB = (9x — 21) cm, OC = (2x —1) cm and OD = 3 cm. Then x = ? | S. 2.1 |
A)
Given that DE||BC,
by B.P.T.,
Let AE = x
Then, from the figure, EC = 5.6-x
5x = 3(5.6-x)
5x = 16.8-3x
8x = 16.8
x = 2.1cm
Therefore, (A)-(s)
B)
As Δ ABCΔDEF,
3EF = 2BC
3EF = 2 × 6
EF = 4cm
Therefore,(B)-(q)
C)
QR =
QR = = 6cm
Therefore (C)-(p)
D)
(BPT)
⇒ 3(2x + 4) = (2x-1)(9x-21)
⇒ 6x + 12 = 18x2-42x-9x + 21
⇒ 18x2-57x + 9 = 0
⇒18x2-54x-3x + 9 = 0
⇒ 18x(x-3)-3(x-3) = 0
⇒ (18x-3)(x-3) = 0
So, x = 3 or x =
But for x = , 2x-1<0 which is not possible.
Therefore, (D)-(r)