This is a basic question from ML aggarwal book of class 10th, chapter 7, ratio and proportion., ICSE board
In this question we have been given that
(4a + 5b) (4c – 5d) = (4a – 5d) (4c + 5d),
And we have to apply mathematical operations to prove that a, b, c, d are in proporton.
Question no 3, 7.3
Solution:
It is given that
(4a + 5b) (4c – 5d) = (4a – 5d) (4c + 5d)
We can write it as
Therefore, it is proved that a, b, c, d are in proportion.