For this case we have to:
x: Represents the unknown number
y: Represents the exponent of base 10
So, considering a system of equations we have:

From the first equation we have:

Substituting in the second equation:

We choose the positive value:

So, the number is 0.4.
So:

Thus, the exponent is 5.
Answer:
Yara use 0.4 and
It wants you to find how much money you will spend a year at each separate gym. That way you can find out which one is cheaper. Once you’ve done that, you need to find how many days it would take for both gym’s cost to be the same after so many days.
Hello,
We see that there is the ratio
2:3:4, which let us to conclude the ratio between the shortest and longest side is 2:4 or 1:2, so the longest side is two times bigger than the smallest.
To find the longest side:
12×2=24 cm. As a result, the length of the longest side is 24 cm. Hope it help!
Answer: 2((x+y)-21)
Calculation/Explanation:
Twice the sum of x and y decreased by 21 means that you must add x and y first before decreasing by 21. The last step is to double the whole equation that we just performed.
Area A of a square with side length a: A = a².
Pythagoras theorem: a² + b² = c²
2*a² = 8²
A = 8²/2