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agasfer [191]
3 years ago
12

Solve this quadratic equation. Show all work. 4x^2-2x-5=0

Mathematics
1 answer:
kicyunya [14]3 years ago
6 0
X= -b⁺₋ √b²-4ac/2a
x= (-(-2)⁺₋√(-2)²- 4(4)(-5))/2(4)
x= 4 ⁺₋√4+80/8
x= (4⁺₋ 9.165)/8
x= 4+9.165)/8 or x= 4-9.165)/8
x= 1.40 or x= -0.896

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The people playing golf hit the golf ball into the green
Fudgin [204]

Answer:

16%

Step-by-step explanation:

4/25 as a percent is 16 % BRAINLEIST PLEASEEEEEE

6 0
3 years ago
Situation:
Rzqust [24]
N=NOe^-kt
N=mass at time t
NO = initial mass
k= 0.1476
t= time, in days

We are asked to find the half-life, which means you want to find how long it will take for half of the substance to decay/disappear (depending on situation). 

If we are looking for half-life, we can simply set N to half of NO (which we are given a value of 40grams for)
Therefore:
N = 20
NO = 40
plugging these values and the value given for k back into the equation you get:

20 = 40e^-0.1476(t)
We are looking for t, so we have to manipulate the formula to get t by itself on one side of the equation.
We can start by dividing 40 from both sides, and you get:
0.5 = e^-0.1476(t)

We have the exponential function "e".
To get rid of e, we can use natural log (ln)
if e^y=x then ln (x) = y
look back at our equation we can set
0.5 = x
-0.1476(t) = y

Rewriting it in natural log form:
ln (0.5) = -0.1476(t)
Plug in ln (0.5) on a calculator to find its value and we get:
-0.693147 = -0.1476(t)
*Note: normally, getting a negative value would suggest that we did something wrong, because you cannot have a negative value as your t (you cannot have negative days), but because there is a negative on both sides of the equation, they will cancel out in this case. 

The last step is to simply divide both sides by -0.1476
therefore:
T = 4.696119
But it asks you for the answer to the nearest tenth (one place after decimal pt) so 
T (half life) = 4.7 days

Hope that helps :)
8 0
3 years ago
A company knows that unit cost C and unit revenue R from the production and sale of x units are related by Upper C equals StartF
levacccp [35]

Answer:

$990 per unit.

Step-by-step explanation:

The Unit Cost (C) and Unit Revenue R from the production and sale of x units are related by the function:

C=\dfrac{R^2}{220000} +3221

We are required to find the rate of change of revenue per unit when the cost per unit is changing by $9 and the revenue is ​$1,000.

Rate of Change of C,

\dfrac{dC}{dt}=\dfrac{R}{110000} \dfrac{dR}{dt} \\\dfrac{dC}{dt}=\$9, R=\$1000\\9=\dfrac{1000}{110000} \dfrac{dR}{dt}\\\dfrac{dR}{dt}=9 \div \dfrac{1000}{110000}\\=9 X  \dfrac{110000}{1000}\\\dfrac{dR}{dt}=\$990 $ per unit$

The Revenue is changing at a rate of $990 per unit.

6 0
3 years ago
Which set of ordered pairs represents y as a function of x?
ikadub [295]

Answer:

{(1, 2), (2, -3), (3, 4), (4, -5)}

Explanation:

The <u>domain</u>, or <u>x-value</u><u>,</u> isn't repeated, while it is in the other answer choices, making the others <u>non</u><u>-</u><u>f</u><u>unctions</u>.

8 0
3 years ago
Let's say we have a box with 6 marbles: 3 red, 1 blue, 1 green, and 1 yellow. What is the probability of picking a yellow marble
Amanda [17]
B. 1/30

Explanation: First you find the probability of picking a yellow marble, 1/6. Then you multiply the probability of picking a blue marble, 1/5 since there are now only five marbles total. Then multiply those to see what the final probability is, 1/6*1/5=1/30.
8 0
3 years ago
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