Answer: 
Step-by-step explanation:
We know that the standard quadratic equation is ax^2+bx+c=0
Let's compare all the given equation to it and , find discriminant.
1. a=2, b= -7, c=-9
So it has 2 real number solutions.
2. a=1, b=-4, c=4
So it has only 1 real number solution.
3. a=4, b=-3, c=-1
So it has 2 real number solutions.
4. a=1, b=-2, c=-8
So it has 2 real number solutions.
5. a=3, b=5, c=3
Thus it does not has real solutions.
This is the formula to solve for the vertex.
Example Question:
Find the vertex of y = -0.5x^2 + 100x
-b/2a = -100/2(-0.5) = -100/-1 = 100
The x coordinate of the vertex is 100.
Best of Luck!
P.S. this is 1000th question i've answered :)
The answer is 35 because 20-10=10 then 25+10=35 so niki made 35 points on her final round
Answer:
hour 3 to hour 4
Step-by-step explanation:
that is where the slope is the least steep
Everything you need is in the picture attached.
