The first two are equivalent to 15 = k + 13
8 = k + 13 - 7 → ( add 7 to both sides )
8 + 7 = k + 13 ⇒ 15 = k + 13 ' is equivalent '
12 = k + 13 - 3 → ( add 3 to both sides )
12 + 3 = k + 13 ' is equivalent '
8
You multiply the numbers
Negative exponents work like this:
So, in order to evaluate a negative exponent, you simply have to invert the base, and then raise to the positive equivalent of the exponent.
As an example, here are the first three exercises:
You can work out the rest applying this logic.
You'd fine the unit rate, in the context of the problem it would be how many minutes it takes for 1 pizza to cook
20/4= 5 minutes for 1 pizza
we are finding how long it would take to cook 10
5 times 10= 50, so 50 minutes
It is 51,600%. Hope it helps
