A radioactive substance decays exponentially. A scientist begins with 350 milligrams of a radioactive substance. After 14 hours, 175 mg of the substance remains. How many milligrams will remain after 20 hours

The value of the unknown number is calculated as - 3

Let the unknown number = y

5  less than the number is written as = y - 5

1 more than three times the number is written as = 1 + 3y

Since the first statement and the second statement are equal, we can equate the two and solve for y.

y - 5 = 1 + 3y

collect similar terms together

y - 3y = 1 + 5

-2y = 6

y = -6/2

y = -3

Therefore, the number is - 3

learn more here: https://brainly.com/question/22548668

Building and solving the expression, it is found that the number is -3.

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They are equivalent, thus:

[tex]x - 5 = 1 + 3x[/tex]

Solving for x.

[tex]3x - x = -5 - 1[/tex]

[tex]2x = -6[/tex]

[tex]x = -\frac{6}{2}[/tex]

[tex]x = -3[/tex]

The number is -3.

A similar problem is given at https://brainly.com/question/20742606

Answer:    The x intercept for Line A is 2  and the x-intercept for line B is -6.

Step-by-step explanation:

Line A uses the equation   y = -1/2x + 1   and to find the x intercept y has to be zero so set the equation equal  0 and solve for x.

0 = -1/2x + 1       Subtract one from both sides

- 1               -1  

-1 = -1/2x              divide both sides by -1/2

x = 2    

So the x intercept for A is   2  

For Line B it already indicates the  x intercept because that is when y is 0. So when  y  is  0  then x is -6.

Answer:

Scalene Right Triangle

Step-by-step explanation:

A possible type of triangle that has no equal sides and one right angle is a right triangle.

Right triangles have just one angle that is equal to 90°, and they can be either isosceles or scalene triangles.

Hope this helped!

Hi there! :)

Answer:

[tex]\huge\boxed{m\leq 2}[/tex]

Equation:

8m - 6 ≤ 10

Add 6 to both sides:

8m ≤ 16

Divide both sides by 8:

8m/8 ≤ 16/8

m ≤ 2

Answer:

8m - 6≤ 10

m≤2

Step-by-step explanation:

8m - 6≤ 10

Add 6 to each side

8m - 6+6≤ 10+6

8m ≤ 16

Divide each side by 8

8m/8 ≤16/8

m≤2

Answer:

Rational, integer, natural, whole, rational numbers

Step-by-step explanation:

17 is a rational, integer, natural, whole, and is a rational number. I'm not totally sure why rational is on there, since rational and rational number should be the same thing. Basically it's everything but "only". If rational is supposed to mean irrational, then it's not irrational.

Answer:

5

Step-by-step explanation:

Use pythagorean theorem. A^2+B^2=C^2

13 is c because it is the hypotenuse and across from the right angle

a is unknown and b is 12

A^2+12^2=13^2

A^2 +144 = 169

A^2 = 169- 144

A^2= 25

now take the sq root of both side

A = 5

Answer:

17.7

Step-by-step explanation:

Answer:

x = 105°

Step-by-step explanation:

The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles

x is an exterior angle of the triangle , then

x = 69° + 36° = 105°

Answer:

Hey there!

We have that 4/5, or 80% of the 60 students passed the exam.

Thus, we have:

0.8(60)=48

48 students passed the exam.

Let me know if this helps :)

Answer:

C

Step-by-step explanation:

Not all real numbers are irrational.

Answer:

358

Step-by-step explanation:

In 1995, the boys were 50 %

Take the number of people at the convention in 1995 ( 716)

and multiply by 50%

716 * 50%

716 * .50

358

Answer:

b. 358

Step-by-step explanation:

First, find what percentage of attendees were boys in 1995:

By reading the graph, we can see 50% were boys.

In the table, we can see that there were 716 attendees in 1995.

To find how many boys attended in 1995, find 50% of 716.

716(0.5) = 358

Answer:

it can be 5 from my side is that right

Answer:

is ur question right

Step-by-step explanation:

is ur question right

is ur question right

is ur question right

x(x+2)+3x+6

x^2+2x+3x+6

x (x+2)+3(x+2)

(x+3) (x+2)

points are

[tex]\boxed{\sf Slope(m)=\dfrac{y_2-y_1}{x_2-x_1}}[/tex]

[tex]\\ \sf\longmapsto m=\dfrac{0-3}{1-0}[/tex]

[tex]\\ \sf\longmapsto m=\dfrac{-3}{1}[/tex]

[tex]\\ \sf\longmapsto m=-3[/tex]

Answer:

y=2x-5

Step-by-step explanation:

First simplify: y-1=2x-6

y-1=2(x-3)

First simplify and distribute everything.

y-1=2x-6

So, x equals 2 because it got distributed into the numbers inside the parenthesis.  Same with the 2 and -3.  They multiplied to become -6.

Since it's y-1=2x-6, you can simplify it even more so the -1 goes to the other side and turns into positive 1.

y - 1 (+ 1) = 2x -6 (+ 1)

-1(+1)=0 which leaves just the variable y on the left side.

-6(+1)=-5 which leaves 2x-5 on the right side.

This results in y=2x-5.  Hope this helped ;)

Answer:

y = 2x - 5

Step-by-step explanation:

y - 1 = 2(x - 3)

y - 1 = 2x - 6

y - 1 + 1 = 2x -6 + 1

y = 2x - 5

Answer:

The middle of the sailboat is approximately 268.8 feet from the shore.

Step-by-step explanation:

Let the distance from shore to the middle of the boat be represented by x, the angle of elevation of Sandra from the shore to the top of the boat mast  is 7°. Applying the required trigonometric function to this question, we have;

Tan θ = [tex]\frac{opposite}{adjacent}[/tex]

Tan 7° = [tex]\frac{23}{x}[/tex]

⇒  x = [tex]\frac{23}{Tan 7^{0} }[/tex]

       = [tex]\frac{23}{0.12279}[/tex]

      = 268.7515

∴ x = 268.8 feet

The middle of the sailboat is approximately 268.8 feet from the shore.

Answer:

[tex]\displaystyle k = \frac{5}{6}[/tex]

Step-by-step explanation:

We are given the equation:

[tex]\displaystyle (2k+1)x^2 + 2x = 10x - 6[/tex]

And we want to find the value of k such that the equation has two real and equivalent roots.

Since the equation is a quadartic, we can find its discriminant (symbolized by Δ). Recall that:

First, rewrite our equation:

[tex](2k+1)x^2 -8x + 6 =0[/tex]

The discriminant is given by:

[tex]\displaystyle \Delta = b^2 -4ac[/tex]

In this case, b = -8, a = (2k + 1), and c = 6.

Therefore, the discriminant is given by:

[tex]\displaystyle \Delta = (-8)^2 - 4(2k+1)(6)[/tex]

For it to have two equal roots, the discriminant must be zero. Hence:

[tex]\displaystyle 0 = (-8)^2 - 4(2k+1)(6)[/tex]

Solve for k:

[tex]\displaystyle \begin{aligned} \displaystyle 0 &= (-8)^2 - 4(2k+1)(6) \\ 0 &= 64 - 48k - 24 \\ 0 &= 40 - 48k \\ -40 &= -48k \\ \\ k &= \frac{5}{6} \end{aligned}[/tex]

Hence, the value of k is 5/6.

Points are

[tex]\\ \sf\longmapsto \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]

[tex]\\ \sf\longmapsto \sqrt{(4+2)^2+(4+2)^2}[/tex]

[tex]\\ \sf\longmapsto \sqrt{6^2+6^2}[/tex]

[tex]\\ \sf\longmapsto \sqrt{36+36}[/tex]

[tex]\\ \sf\longmapsto \sqrt{72}[/tex]

[tex]\\ \sf\longmapsto 8.4[/tex]

Answer:

- 1

Step-by-step explanation:

The average rate of change of g(x) in the close interval [ a, b ] is

[tex]\frac{g(b)-g(a)}{b-a}[/tex]

Here [ a, b ] = [ 3, 6 ] , then

g(b) = g(6) = 6² - 10(6) + 19 = 36 - 60 + 19 = - 5

g(a) = g(3) = 3² - 10(3) + 19 = 9 - 30 + 19 = - 2

average rate of change = [tex]\frac{-5-(-2)}{6-3}[/tex] = [tex]\frac{-5+2}{3}[/tex] = [tex]\frac{-3}{3}[/tex] = - 1

Answer:

3^2  = 9

(-4+5)^2-11+2^3 = -2

-2/9 or -9/2 ... re-read question is 3^2 dividing into (-4+5)^2-11+2^3

or the other way around... I think that there is a missing word...

3^2 "divided into"

vs 3^2 "divided by"

Step-by-step explanation:

Answer:

Hope it helps

Step-by-step explanation:

a)= 1 grade = 9/10 degree

150 = 9/10 × 150 degree

= 135 degree

b ) = solution

x+3 = 6

so, x = 3

y = 4

c) = let the unknown angle be x

now,

converting 60 grades into degree

= 60×9/10

= 54°

now

54° + 90° + x = 180°

144°-180° = -x

so, x = 36°

Answer:

prime

Step-by-step explanation:

3x^2 + 5x + 1

3x^2  factors in to 3x and x

1 factors into 1 and 1

( 3x   + 1) ( x+1)

We need to verify the middle is 5

3x+1x = 4x

so this is not true

We cannot factor this so it is prime

Answer:

[tex]\large \boxed{\sf Prime}[/tex]

Step-by-step explanation:

[tex]3x^2 + 5x + 1[/tex]

We need to find two numbers that add to 5 and multiply to get 1.

There are no real numbers.

The expression cannot be factored. The expression is prime.

Answer:

Step-by-step explanation:

These are geometric means problems. In the top one, a is the geometric mean as the height for both the smaller triangles inside the big one. Therefore,

[tex]\frac{4}{a} =\frac{a}{25\\}\\a^2=100\\a=10[/tex]

The next one has the geometric mean of b, being a part of the smaller triangle on the left and the big triangle as a whole:

[tex]\frac{4}{b} =\frac{b}{29}\\b^2=116\\b=10.77[/tex]

Answer:

1.35

Step-by-step explanation:

Answer:

Amplitude = 2

Step-by-step explanation:

The amplitude of this sine wave is 2 denoted by the coefficient -2 in front of the sin(x).  The negative of the coefficient denotes that the sine wave is the opposite of the standard sine wave.

Cheers.

Answer:

201, 206, 216, 228, 240

Step-by-step explanation:

Answer:

Step-by-step explanation:

Let the mass of the metal be x

From the question

5/9 of the metal is 7kg

That's

[tex] \frac{5}{9} x = 7[/tex]

Multiply through by 9

We have

5x = 7 × 9

5x = 63

Divide both sides by 5

[tex] \frac{5x}{5} = \frac{63}{5} [/tex]

We have the final answer as

x = 12.6 kg

Hope this helps you

Answer:

18. [tex] x = 8 [/tex]

19. [tex] c = 9 [/tex]

20. [tex] d = \sqrt{10} [/tex]

21. 83 1/3 ft

22.

a. decay

b. growth

c. decay

Step-by-step explanation:

18.

[tex] \sqrt{x + 1} + 12 + 10 = 25 [/tex]

[tex[ \sqrt{x + 1} = 3 [/tex]

Square both sides.

[tex] x + 1 = 9 [/tex]

[tex] x = 8 [/tex]

19.

[tex] a^2 + b^2 = c^2 [/tex]

[tex] (\sqrt{75})^2 + (\sqrt{6})^2 = c^2 [/tex]

[tex] 75 + 6 = c^2 [/tex]

[tex] 81 = c^2 [/tex]

[tex] c = 9 [/tex]

20.

[tex] d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} [/tex]

[tex] d = \sqrt{(3 - 4)^2 + (-9 - (-6))^2} [/tex]

[tex] d = \sqrt{(-1)^2 + (-3)^2} [/tex]

[tex] d = \sqrt{1 + 9} [/tex]

[tex] d = \sqrt{10} [/tex]

21.

Max: 5 ft tall; 3 ft shadow

Building: x ft tall; 50 ft shadow

5 ft is to 3 ft as x ft is to 50 ft

5/3 = x/50

3x = 250

x = 250/3

x = 83 1/3

Answer: 83 1/3 ft

22.

Exponential function:

y = a(b)^x

b is the number in parentheses raised to exponent x.

If b > 1, it is growth.

If b is between 0 and 1, it is decay.

Look at each case.

a. 0.85 is between 0 and 1: decay

b. 1.025 > 1: growth

c. 0.682 is between 0 and 1: decay

Answer:

Local Maximum Approx.: (1,8.08)

Local Minima Approx.: (-2,-7.67) and (3,2.75)

Step-by-step explanation:

Local maximums and minima there the highest and lowest points, respectively, on a graph in a specific region. (This is different from absolute maximum and minimum, which are the highest and lowest points overall.)

These are pretty clear to see on a curve, as they are the "turns" or the points where the curve switches direction from up to down or down to up.

On your graph, we have two local minima and one local maximum. The local minima are at x= -2 and x=3. The local maximum is at x=8. Because of the way the graph is, we have to approximate the y-values of each point.

The answer option which best describes this is the third option, so that is your answer.