Question

7a+4 x 5b = 1715 ab = (a) 0 (b) 2 (c) -1 (d)4

Answer 1

Answer:

please write proper question

Answer 2

Answer:

c) -1

Step-by-step explanation:

Correcting the question.

7^(a+4) x 5^b = 1715, then ab = ?

1715 will get factorized as 7 x 7 x 7 x 5

So, 7³ . 5¹ = 1715 = 7^(a+4) . 5^b

So, a+4 = 3, hence a = -1

b = 1

ab = -1.1 = -1

So the correct answer is c) -1