since this is a multiplication, all the numerators are just factors of the product numerator and all denominators are just factors of the product denominator, so we can simply reorder them some, without changing the product.
Answer:
-3
Step-by-step explanation:
Let x equal the mystery number
Our equation will be:
x - 5 = 1 + 3x
Subtract x from both sides
-5 = 1 + 2x
Subtract 1 from both sides
-6 = 2x
Divide both sides by 2
-3 = x
When you multiply a same number but with different powers, you can simply add the powers together. So, in your question, add the powers -1 and -7 together.
7^(-1) x 7^(-7) = 7^(-8)
When you divide a same number but with different powers, you subtract the power at the top with the power from the denominator. So, -8 - (-7) = -1.
7^(-8) / 7^(-7) = 7^(-1)
So your answer would be 7^(-1).
Hopefully my explanation was clear?