Need help ASAP

Solve the following quadratic by factoring.

Lina20 [59]

Answer:

4, -1

Step-by-step explanation:

We can reverse the FOIL (First, outside, inside, last) method to break down the equation. The question is asking to solve by factoring so you want to find the right combination of numbers this equation can be broken down into:

x^2 - 3x - 4 = 0

Because we want x squared, x needs to be multiplied by itself, so we can put x in the first slot for each.

(x + or - ?) ( x + or - ?) = 0

Then we need to find numbers that could be added to get -3 and multiplied to get -4. The only set of numbers that works for this is -4 and 1. Note that the sign you put in front of each number has an impact on your answers. With this we get:

(x - 4) (x + 1) = 0

To test that this is equal to the original equation, simply multiply it out using FOIL.

x * x = x^2

x * 1 = x

x * -4 = -4x

-4 * 1 = -4

Putting each component into an equation:

x^2 + x - 4x - 4 = 0

Simplifying:

x^2 - 3x - 4 = 0

Once we are sure it is still the same equation, we find the solutions. We know 0 multiplied by anything equals 0, so to get 0 as the answer, one of the sets in the parentheses must equal 0. (It doesn't matter what the other one is as long is one equals 0)

Therefore, we have 2 solutions, 4, and -1 because if x is 4, 4-4 is 0 which solves the equation, and if x is -1, then -1 + 1 is 0 which also solves the equation.

You can also check your answers by plugging them back into the original equation.

5 0

3 years ago

If one three-digit number ( 0 cannot be a left digit) is chosen at random from all those that can be made from the following set

Oksana_A [137]

The probability of choosing a number that is not a multiple of 2 is P = 0.44

<h3 /><h3>How to find the probability?</h3>

We need to count the number of options for each digit.

For the first digit, we have 8 options {1, 2, 3, 4, 5, 6, 7, 8}
For the second digit, we have 9 options {0 ,1, 2, 3, 4, 5, 6, 7, 8}
For the third digit, we have 9 options {0 ,1, 2, 3, 4, 5, 6, 7, 8}.

The total number of combinations is the product between the numbers of options:

C = 8*9*9 = 648

If we want our number to not be a multiple of 2 then it must end in a odd digit, the combinations that meet that condition are:

For the first digit, we have 8 options {1, 2, 3, 4, 5, 6, 7, 8}
For the second digit, we have 9 options {0 ,1, 2, 3, 4, 5, 6, 7, 8}
For the third digit, we have 4 options {1, 3, 5, 7}.

C = 8*9*4 = 288

Then the probability of selecting a 3 digit number that is not a multiple of 2 is:

P = 288/648 = 0.44

If you want to learn more about probability, you can read:

brainly.com/question/251701

8 0

2 years ago

Explain a real life situation where you may use trig ratios to find measure in right triangles.

OLEGan [10]

One example is if you wanted to measure the height of a tall building. You'll need to measure the distance from where you're standing to the base of the building. You'll also need the angle of elevation. To get the angle of elevation, start by looking completely horizontal, then tilt upward until your eyeline reaches the top of the building. Once you have those two things (the side and angle) you can use the tangent ratio to find the height. This is because

tan(angle) = opposite/adjacent

where in this case
angle = angle of elevation
opposite = height of building
adjacent = distance from your position to the base of the building

It takes a bit of algebra, but the opposite side can be solved for. You'll most likely need a calculator to compute the tangent ratio.

5 0

3 years ago

Your height is 5 feet and 1 5/8 inches. Your friend’s height is 5.6 feet. Who is taller?

Alex Ar [27]

Not your friend you cause if you add 5 ft+1 5/8 it’s gonna be more than 5.)

7 0

3 years ago

Gravel is being dumped from a conveyor belt at a rate of 10 cubic feet per minute. It forms a pile in the shape of a right circu

Sunny_sXe [5.5K]

Answer:

0.0221 feet per minute.

Step-by-step explanation:

$\text{Volume of a cone}=\dfrac{1}{3}\pi r^2 h$

If the Base Diameter = Height of the Cone

The radius of the Cone = h/2

Therefore,

$\text{Volume of the cone}=\dfrac{\pi h}{3} (\dfrac{h}{2}) ^2 \\V=\dfrac{\pi h^3}{12}$

Rate of Change of the Volume, $\dfrac{dV}{dt}=\dfrac{3\pi h^2}{12}\dfrac{dh}{dt}$

Since gravel is being dumped from a conveyor belt at a rate of 10 cubic feet per minute. Therefore, the Volume of the cone is increasing at a rate of 10 cubic feet per minute.

$\dfrac{dV}{dt}=10$ ft^3/min$

We want to determine how fast is the height of the pile is increasing when the pile is 24 feet high.

We have:

$\dfrac{3\pi h^2}{12}\dfrac{dh}{dt}=10\\\\$When h=24$ feet$\\\dfrac{3\pi *24^2}{12}\dfrac{dh}{dt}=10\\144\pi \dfrac{dh}{dt}=10\\ \dfrac{dh}{dt}= \dfrac{10}{144\pi}\\ \dfrac{dh}{dt}=0.0221$ feet per minute$

When the pile is 24 feet high, the height of the pile is increasing at a rate of 0.0221 feet per minute.

4 0

3 years ago