-3(2x^2+ax+b)=-6x+12x-15 what is the value of a and b

Joe began to increase the speed of his car at 2:00 P.M. Since that time,the speed of Joes car has been steadily increasing by 1

Olegator [25]

Answer:

7 mins

Step-by-step explanation:

Current speed of Joes Car = 65.5 mph

We have to find the time interval for which the car exceeded the speed limit of 55 mph.

While, we are given that the speed of the car was constantly increasing, hence the speed over all increased from the limit of 55 mph = 65.50-55.00 = 10.50 mph

We are also given that Joes car was increasing speed at a constant rate of 1.50 mph for every passing minute. Hence

1.50 mph is increased in 1 minute

1 mph will be increase in $\frac{1}{1.5}$ minutes

Hence

10.50 mph will be increased in $\frac{1}{1.5} \times 10.50$ minutes

$= \frac{10.5}{1.5}$

$=7$

Hence joes car was exceeding the limit of 55 mph for 7 minutes.

8 0

3 years ago

1-Describe the error in the way the calculation of the slope of the two points is set up and/or solved. Please be specific. Do n

Bad White [126]

Answer:

Please check explanations for answer

Step-by-step explanation:

Let’s have two points (5,10) and (15,20)

1. Let’s find the slope of these two points

Mathematically, the slope can be calculated using the formula;

m = (y2-y1)/(x1-x2)

So m = (20-10)/(5-15) = 10/-10 = -1

The error here is the formula used in calculating the slope

The formula should be;

m = (y2-y1)/(x2-x1) and not x1-x2

2. To calculate the slope correctly, we have;

m = (y2-y1)/(x2-x1)

So the slope will be;

m = (20-10)/(15-5) = 10/10 = 1

In the point slope form, the equation can be represented as;

y-y1 = m(x-x1)

Let’s use the point (5,10)

y- 10 = 1(x-5)

The above is the point slope form

using one of the points and the correct slope of the line

6 0

3 years ago

4. The reflecting dish of a parabolic microphone has a cross-section in the shape of a parabola. The microphone itself is placed

elixir [45]

Assume the parabola is placed on a graph where the x-axis is the top of the dish.
The vertex is then at (0,-30) The x-intercepts or zeros are at (-30,0) and (30,0)

The equation of such parabola would be:
$y = a(x+30)(x-30)$
Plug in vertex to find value of 'a'
$-30 = a(0+30)(0-30) \\ \\ a = \frac{-30}{(-30)(30)} = \frac{1}{30}$

Now find the focus given that $p = \frac{1}{4a}$
$p = \frac{1}{4(1/30)} = \frac{30}{4} = 7.5$

Answer: the microphone should be placed 7.5 inches from vertex.

8 0

3 years ago

Okay here's the first few questions

Marina86 [1]

Answer:

1,yes

2,no

3,x=√117

4,x=12 y=6

5,x=12, y=15.75

6 0

3 years ago

List all the factors of 10

saul85 [17]

Answer: factors of 10 are 1, 2, 5, and 10.

Step-by-step explanation: You can also look at this the other way around: if you can multiply two whole numbers to create a third number, those two numbers are factors of the third. 2 x 5 = 10, so 2 and 5 are factors of 10.

8 0

3 years ago

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