What is the sum of two consecutive even numbers, the difference of whose squares is 84?
A. 34
B. 38
C. 42
D. 46
Answer: Option C
Solution (By Examveda Team)
Let the numbers be x and x + 2.Then, (x + 2)2 - x2 = 84
⇒ 4x + 4 = 84
⇒ 4x = 80
⇒ x = 20.
∴ The required sum
= x + (x + 2)
= 2x + 2
= 42
This Question Belongs to Arithmetic Ability >> Problems On Numbers
I can't understand please explain.
(x+2)^2- x^2= 4x+4