Question

Find the missing term.

Answer 1

Find the missing term.7-147 × 798 = 718 × 7-38 × M
7^-147 * 7^98 = 7^18 * 7^-38 * M
7^(-147+98) = 7^(18 + -38)
7^-49 = 7^-20 * M
M = 7^-49 / 7^-20
M = 7^(-49 + 20)
M = 7^-29

So the correct answer is C.7^(-29) 

Answer 2

Answer: Option 'C' is correct.

The missing term is $7^{-29}=x$

Step-by-step explanation:

Since we have given that

$7^{-147}\times 7^{98}=7^{18}\times 7^{-38}\times x$

We need to find the missing part i.e. x.

We will use "Exponential law " :

$a^m\times a^n=a^{m+n}$

So, it becomes,

$7^{-147}\times 7^{98}=7^{18}\times 7^{-38}\times x\\\\7^{-147+98}=7^{18-38}\times x\\\\7^{-49}=7^{-20}\times x\\\\7^{-49}\div 7^{-20}=x\\\\7^{-49-(-20)}=x\\\\7^{-49+20}=x\\\\7^{-29}=x$

Hence, the missing term is $7^{-29}=x$

Therefore, Option 'C' is correct.