Question

find the value of x,if 7^x*7^-3=7^5.

Answer 1

${7}^{x} \times {7}^{ - 3} = {7}^{5}$

We know that a^m * a^n = a^m+n .

${7}^{x - 3} = {7}^{5}$

As bases are equal, Equate the powers.

$x - 3 = 5$

$x = 5 + 3$

x = 8 .

Therefore Value of x is 8 .

Answer 2

7^×*7^-3=7^5
(7)^(×+(-3))=7^5
bases are same so we equate their powers
x+(-3)=5
×-3=5
×=5+3
×=8