there are two numbers such that the sum of the numbers is 48 and their difference is 8 find the difference of their squares
Answers
x+y=48,x-y=8 (if one is x,& other is y) then,
x=8+y,
8+y+y=48,
8+2y=48,
y=(48-8)/2=20,
x=20+8=28
difference of squares= (28×28)-(20×20)= 784-400=384
Given
- There are two numbers
- The sum of the numbers is 48.
- The difference of the numbers is 8.
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To Find
- Difference of their squares.
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Solution
Let one of the numbers be 'x' and the other be 'y'.
x + y = 48 (i)
x - y = 8 (ii)
Let's take equation (i)
⇒ x + y = 48
⇒ x = 48 - y
With the value of 'x' let's find value of equation (ii)
⇒ (48 - y) - y = 8
⇒ 48 - y - y = 8
⇒ 48 - 2y = 8
⇒ 48 - 8 = 2y
⇒ 40 = 2y
⇒ y = 40 ÷ 2
⇒ y = 20
With the obtained value of 'y' let's find the value of 'x'.
⇒ x + 20 = 48
⇒ x = 48 - 20
⇒ x = 28
∴ x = 28 and y = 20
Now let's find the difference of their squares.
⇒ (28)² - (20)²
⇒ 784 - 400
⇒ 384
∴ The difference of their squares is 384.
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