The equation in standard form is 2x^2 + 7x - 15=0. Factoring it gives you (2x-3)(x+5)= 0. That's the first one. The second one requires you to now your formula for the axis of symmetry which is x = -b/2a with a and b coming from your quadratic. Your a is -1 and your b is -2, so your axis of symmetry is
x= -(-2)/2(-1) which is x = 2/-2 which is x = -1. That -1 is the x coordinate of the vertex. You could plug that back into the equation and solve it for y, which is the easier way, or you could complete the square on the quadratic...let's plug in x to find y. -(-1)^2 - 2(-1)-1 = 0. So the vertex is (-1, 0). That's the first choice given. For the last one, since it is a negative quadratic it will be a mountain instead of a cup, meaning it doesn't open upwards, it opens downwards. Those quadratics will ALWAYS have a max value as opposed to a min value which occurs with an upwards opening parabola. This one is also the first choice because of the way the equation is written. There is no side to side movement (the lack of parenthesis tells us that) so the x coordinate for the vertex is 0. The -1 tells us that it has moved down from the origin 1 unit; hence the y coordinate is -1. The vertex is a max at (0, -1)
Answer:
The estimated average electric cost amount of all residents in Las Cruces = 182.9
Step-by-step explanation:
The bill amounts from the electric company for the month of July for 10 randomly selected houses from the map was obtained to be
135 265 215 103 156 203 125 156 230 241
Using the Central Limit theory, the mean of a sample extracted randomly from an independent distribution is approximately equal to the population mean of the independent distribution.
This means that the sample mean of a random sample extracted from the population is a good estimate of the population mean.
Sample mean ≈ Population mean
μₓ = μ
Mean = = (Σx)/N
The mean is the sum of variables divided by the number of variables
x = each variable
N = Sample size = 10
Σx = (135+265+215+103+156+203+125+156+230+241) = 1,829
Sample mean = (1,829/10) = 182.9
Population mean ≈ sample mean
Population mean ≈ 182.9
Hope this Helps!!!
Answer:
15 gallons PLEASE GIVE BRAINLIEST
Step-by-step explanation:
55 x 6 = 330 total miles
330 ÷ 22 = 15 gallons of gas are needed
Answer:
4
Step-by-step explanation:
You take 3/4 + 3/4 and add it. That equals 1.5, so you take 3/4+ 3/4 again and you get 1.5 . So, 1.5+1.5 is 3. So that's how you get your total of 4 boxes.
Answer:
(a) (-∞, -8) (-6, -4) (-2, ∞)
(b) -6, -2
(c) negative
(d) 5
Step-by-step explanation:
(a) A function is "decreasing" when the y-value decreases as the x-value increases.
⇒ the function is decreasing over these intervals : (-∞, -8) (-6, -4) (-2, ∞)
(b) Local maxima are the points on the function where it reaches a maximum.
⇒ maxima at x = -6 and x = -2
(c) negative
(d) 5
