Question

If 2^n-7 x 5^n-4 = 1250, find the value of n.
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Answer 1

Step-by-step explanation:

2^n-7×5^n-4=1250

(2×5)^n-7+n-4=1250

(10)^n-7+n-4=1250

n-7+n-4=1250

2n-3=1250

2n =1250+3

n =1253/2

n=626.5

Answer 2

Answer:

Q. 2^n-7x 5^n-4=1250

Step-by-step explanation:

1) 2^n-7 x 5^n-4=1250 can be written as

2^n-7 x 5^n-7 x 5^3 =1250

2) Now we can take 2^n-7 and 5^n-7 common

Therefore,

(2x5)^n-7 x 5^3=1250

3) Solving the bracket

(10)^n-7 x 5^3=1250

4) Sending 5^3 to the other side

(10)^n-7 =1250/5^3

=(10)^n-7 =1250/125

5) Solving the RHS

(10)^n-7 =(10)^1

6 )Constant is same,Now we can determine the

powers

n-7=1

n=1+7

n=8