the sum of the digit of two digit no. is 7. The difference of the square of the no. and the no. obtained by interchanging the digits is 195. Find the no.
Answers
Answered by
0
Answer:
6&34--:&-7434-+-54225888++-23556+++4664237
Answered by
7
Let the digits be x and y
Digits in the ones place = y
Digits in the tens place = x
Hence the number will be 10x+y
digit interchanged number or reversed number will be 10y+x
By the given conditions,
x+y = 7
y = 7-x ------(1)
(10x+y)² - (10y+x)² = 195
100x² + y² + 20xy - 100y² - x² - 20xy = 195
99x² - 99y² = 195
33x² - 33y² = 65
33(x²-y²) = 65 --------(2)
Substituting (1) in (2)
33[x²-(7-x)²] = 65
33(x²-49-x²+14x) = 65
33(14x-49) = 65
462x - 1617 = 65
462x = 1682
x = 1682/462 ≈ 3
y = 7-3
y = 4
Therefore the number is 30+4 = 34
Hope this is helpful to you
Pls mark as brainliest
Follow me and I'll follow you back
Similar questions