Answer should be C. If you simplify the vertex equation y=7(x+1)^2 -3, you end up with the standard equation.
y=7(x^2 + 2x + 1) -3
y= 7x^2 + 14x + 7 - 3
y= 7x^2 + 14x + 4
ANSWER

EXPLANATION
We determine the slope of each line using the slope formula;

The slope of BC is


The slope of AB is


The two lines are perpendicular so the product of their slopes is -1.

This implies that,




.
Which question? I'm a little bit confused :(
Answer:
It's C, 3
Step-by-step explanation:
Just did the problem and got it right :]