Question

4) Find the value of k if -2^k * -2^3 = -2^7

Answer 1

Answer:

-2^k*-2^3=-2^7

k+3=7 ( when the base is same the exponents gets summed)

k=7-3

k=4

Answer 2

$\sf\huge {\underline{\underline{{Solution}}}}$

=> -2^k * -2^ 3= -2^7

since , bases are same on both sides

Concept:

If two numbers having same base then their powers gets added during multiplication and gets substracted during Division.

=> -2^k+3= -2^7

on comparing the powers both sides we get ,

=> k+3= 7

=> k= 7-3 = 4

k= 4

Check:

=> -2^4*-2^3

=> -2^4+3= -2^7

More information=>

• If two different numbers having same power are in Multiply then : a^m*b^m = (ab)^m and in Division (a/b)^m
• Any value having power 0 treated as 1.