The difference between two numbers is 14 and the difference between their squares is 448, then find the numbers
Answers
Answer:
Step-by-step explanation:
Let the two numbers be x and y respectively.
Given that ;
The difference between the two numbers is 14.
⇒ x - y = 14.... (i)
Difference between their squares is 448.
⇒ x² - y² = 448
⇒ (x + y)(x - y) = 448
⇒ (x + y) * 14 = 448
⇒ x + y =
⇒ x + y = 32 .....(ii)
_______________________
On adding equation (i) and (ii) -
⇒ x - y + x + y = 14 + 32
⇒ 2x = 46
⇒ x =
⇒ x = 23
Substituting the value of x in (i)
⇒ x - y = 14
⇒ 23 - y = 14
⇒ y = 23 - 14
⇒ y = 9
_______________________
Hence, the two required numbers are 23 and 9.
===================
Given :
1. The difference between
two numbers is 14
2. The difference between
their squares is 448.
===================
To find :
Required number.
===================
Let us take :
Let the two number be
'x' and 'y'.
===================
Difference of between two numbers
⇒ x - y = 14
===================
Difference between their square
⇒ x² - y² = 448
Here, an identity is used
⇒ x²-y² = (x+y) (x-y)
⇒ (x+y) (x-y) = 448
⇒ (x+y) × 14 = 448 (Value of x-y is 14)
⇒ x+y =
⇒ x+y = 32
Here we get the value
of x+y which is 32
===================
Now we have to add
x-y and x+y to find the value
of 'x' and we have
the value of x-y which is
14 and value of x+y which is
32.
Let us add
⇒ x + y + x - y = 14 + 32 ( y-y will be cancelled )
⇒ 2x = 14 + 32
⇒ 2x = 46
⇒ x = 46/2
⇒ x = 23
Here we get the value
of 'x' which is 23
===================
To find the second number
we have to put the value
of 'x' in (x - y = 14)
Let us put the
value of 'x' in
x - y = 14
⇒ x - y = 14
⇒ 23 - y = 14
⇒ 23 - 14 = y
⇒ 9 = y
Therefore value of y is 9
Here we get the value of 'y'
which is 9