The answer is c you must look at key words i learned my key words
180a^3+900a^3+4a-5
__________________ + a-1/ 6a^a
6a ( a+ 5)
Let x is the first no. then the other no. will obviously be (x+1)
according to question,
(x+1)²- x²= 15
x² +2x+1 - x² = 15 ( using (a+b)²= a²+ b² + 2ab )
2x + 1 = 15
2x = 14
x = 7
hence numbers are x = 7 and x +1 = 7+1 = 8
also 8²-7² = 64-49 = 15
hence the numbers are 7 and 8
hope it helped