7x−1+11x−1=170 Let the value of x = 3 So, 73−1+113−1=170 72+112=170 49+121=170 170=170 Hence, x = 3 satisfies the given conditions. If the value of x is greater or less than 3, then R.H.S is not equal to 170. Hence, only one solution of the given equation exists.