Answer:
vertex = (- 1, 1 )
Step-by-step explanation:
Given a parabola in standard form
y = ax² + bx + c ( a ≠ 0 )
Then the x- coordinate of the vertex is
x = - 
y = x² + 2x + 2 ← is in standard form
with a = 1 and b = 2 , then
x = -
= - 1
substitute x = - 1 into the equation for y- coordinate of vertex
y = (- 1)² + 2(- 1) + 2 = 1 - 2 + 2 = 1
vertex = (- 1, 1 )
Answer:
The original price of the laptop is 840
Step-by-step explanation:
Here, we want to calculate the original price of a laptop, given the amount that was paid off and the discount percentage enjoyed.
Firstly, let’s add back the 50 taken off. That makes a total of 50 + 664 = 714
Now, we remember he was also given 15% off. Let the price paid be x;
The 15% of x is equal the difference between x and the 714
Thus;
15/100 * x = x - 714
15x/100 = (x-714)
15x = 100(x-714)
15x = 100x -71400
100x-15x = 71400
85x = 71400
x = 71400/85
x = 840
Answer:
-5
Step-by-step explanation:
The initial value would be the value when x=0. Substituting 0 for x,
y = -2(0)-5
y = 0 - 5
y = -5