ABCD is a quadrilateral in which AD = BC and ∠ DAB = ∠ CBA (see Fig. 7.17). Prove that
(i) ∆ ABD ≅ ∆ BAC
(ii) BD = AC
(iii) ∠ ABD = ∠ BAC.

In ∆ABD and ∆BAC,
AD = BC (Given)
∠DAB = ∠CBA (Given)
AB = BA (Common)
∴ ∆ABD ≅∆BAC (By SAS congruence rule)
∴ BD = AC (By CPCT) And, ∠ABD
= ∠BAC (By CPCT)
Length (in hours) | Number of lamps |
|---|---|
300 − 400 | 14 |
400 − 500 | 56 |
500 − 600 | 60 |
600 − 700 | 86 |
700 − 800 | 74 |
800 − 900 | 62 |
900 − 1000 | 48 |
(i) Represent the given information with the help of a histogram.
(ii) How many lamps have a lifetime of more than 700 hours?
Why was Santosh sent to the local school?