Question

if 3^n-4*7^n-3=7 then by using laws of exponents find the value of n

Answer 1

Answer:

n=4

Step-by-step explanation:

• 3^n-4*7^n-3=7              divide both sides by 7
• 3^n-4*7^n-4=1              
• 21^n-4 = 1
• 21^n-4= 21^0
• n-4=0
• n= 4

Answer 2

Answer:

2

n−7

×5

n−4

=1250

2

n−7

×5

n−7

×5

3

=1250

⇒(2×5)

n−7

=

125

1250

⇒10

n−7

=10

1

⇒n−7=1

⇒n=7+1=8