Question

2 ^n-5×5^n-4 = 5 find the value of n​

Answer 1

Answer:

Step-by-step explanation:

The value of n is

(i) 2.75

(ii) 0.54

Given equation is :

       (2n-5) × (5n-4) = 5

        10n² -8n -25n +20 = 5

        10n²-33n +15 = 0

Here, a= 10, b= -33, c= 15

Now,

       D= b²-4ac

          = (-33)² - 4(10 * 15)

          = 1089-600

          = 489

Roots:

 and

Upon putting the values and solving we get,

       n= 2.75 and 0.54

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