Answer:
1
Step-by-step explanation:
21/21 is whole and the a whole as a whole number is equivalent to 1.

Cross multiply.
5.4x=9*25.8
5.4x=232.2 Divide both sides by 5.4
x=43
Multiply 400 times 0.70 and that’s how you get the % (in this case 280)
To find the zeros of this function, we must first set the entire function equal to 0
f(x) = x² - 2x - 15 = 0
Since this is a quadratic function, we must use the quadratic formula, which is:

Let's assign a, b, and c using our first function
x² means a = 1 (because it could be written as 1x²)
-2x means b = -2
-15 means c = -15
Now let's plug those in:

which simplifies to:

Simplified further:


And divide it by the 2 on the bottom gives us:

2+4 = 6
2-4 = -2
So the zeros of this function are
-2 and
6