the lcm of two consecutive even number is 180. find the number
Answers
Answer:
Let the number be 2x and 2x+2
A/q,
2x(x+1) = 180
x²+x-90 = 0
x²+10x-9x-90 = 0
x(x+10)-9(x+10) = 0
(x+10)(x-9) = 0
x = 9
Numbers are = 18 & 20 . (Ans)
Answer:
★First number = 18 and Second Number = 20 ★
Step-by-step explanation:
Given:
- LCM of consecutive even numbers is 180
To Find: Find the two consecutive even numbers
Solution: Let the 1st consecutive even number is 2x and 2nd consecutive even number is 2x + 2
→ If ‘a’ and ‘b’ are two numbers, then their product is equal to the product of their LCM and HCF
→We can logically say that the HCF of any two consecutive even numbers is always equal to ‘2’ provided that the smallest no. is at least ‘2’.
According to the question
2x (2x + 2 ) = HCF x LCM
4x² + 4x = 2 x 180
x² + x = 90
x² + x – 90 = 0
★By middle term Splitting★
x² + 10x – 9x – 90 = 0
x(x + 10) – 9(x+10) = 0
(x+10)(x–9)
So, x = 9 and –10( Discard –10 because it is negative)
∴ Numbers = 2x = 2 x 9 = 18
and 2x + 2 = 2 x 9 + 2 = 10+2 = 20