The equality used is Subtraction property of equality
Option A is correct
Step-by-step explanation:
We need to identify which option best explains or justifies Step 1.
Step 1 is: 
The given equation is: 
To get the equation for step 1 we need to subtract c on both sides of equation i.e using subtraction property of equality


So, The equality used is Subtraction property of equality
Option A is correct.
Keywords: Solving Quadratic Equations
Learn more about Solving Quadratic Equations at:
#learnwithBrainly
Solution :
Given the equation :




n = 9



Therefore the vertex form of
is
.
This cannot be fit into a normal distribution. While the first 7 runners all have times relatively close, the time of the last runner is an outlier, as it is too far from the other data points. The standard deviation is calculated by taking the mean, subtracting each value from the mean, squaring the deviations, adding these, then dividing by the number of data points (7), and taking the square root. This gives an answer of SD = 0.1107.
Your answer is B. You multiply 5 by the exponents and 4^0 is just 1, so 4^45•1=4^45. Hope this helped!