in a parallelogram abcd , ab=10and the altitude corresponding to the sides ab and ad are respectively 7cm and 8 cm ,find ad
Answers
Question:
In a parallelogram ABCD , AB = 10 cm and the altitudes corresponding to the sides AB and AD are respectively 7cm and 8 cm , find AD .
Answer:
AD = 8¾ cm OR 8.75 cm
Note:
• A parallelogram is a quadrilateral whose opposite sides are parallel and equal .
• The two diagonals of parallelogram bisect each other.
• The area of a parallelogram = Base•Altitude
Solution:
Let DL be the altitude corresponding to the side AB and BM be the altitude corresponding to the side AD .
According to the question,
The altitudes corresponding to the sides AB and AD are 7cm and 8 cm respectively.
Thus,
DL = 7 cm
BM = 8 cm
Now,
When AB is taken as base and DL is taken as altitude, then the area of parallelogram ABCD will be given as ;
=> Area = AB × DL
=> Area = 10 × 7
=> Area = 70 cm² ------(1)
Also,
When AD is taken as base and BM is taken as altitude, then the area of parallelogram ABCD will be given as ;
=> Area = AD × BM
=> Area = AD × 8
=> Area = 8•AD cm² ------(2)
Now,
From eq-(1) and eq-(2) , we have;
=> 70 = 8•AD
=> AD = 70/8
=> AD = 35/4 cm
=> AD = 8¾ cm
=> AD = 8.75 cm
Hence,
The required value of AD is 8¾ cm OR 8.75 cm
ABCD is a parallelogram such that AB = CD and AC = BD.
Lenght of AD.
So ,
Area of parallelogram = XD × AB
Area of parallelogram = 10 × 7
Area of parallelogram = ....... (1)
Now,
In parallalogram ABCD = AD × 8 ........(2)
From equations 1 and 2 we get.
AD × 8 = 70
AD = 70/8 =