Answer:
Its usual speed is 25 kilometre/hour
Step-by-step explanation:
Let the usual time duration for a journey of 300 km. = t
Let the usual speed = v
The parameters given are;
The time duration for the 300 km. journey at increased speed = t - 2
The increased speed of the passenger train = v + 5
Distance, d = Speed, v × Time, t
Therefore, we have;
v × t = 300
∴ t = 300/v
Also (v + 5)×(t - 2) = 300
Substituting the value of t = 300/v, we have;
(v + 5)×(300/v - 2) = 300
[tex]- \dfrac{2 \cdot v^2 - 290 \cdot v - 1500}{v} = 300[/tex]
Which gives;
2·v² + 10·v - 1500 = 0
Which is equivalent to v² + 5·v - 750 = 0
Therefore we have;
(v + 30)·(v - 25) = 0 whereby v = -35 or 25 km/h
v = Natural number = 25 km/hour
Therefore its usual speed is 25 kilometre/hour.
A line passes through point (5, –3) and is perpendicular to the equation y = x. What's the equation of the line?
Answer:
y = -x +2
Step-by-step explanation:
y =x has a slope of 1
Perpendicular lines have slopes that multiply to -1
m* 1 = -1
The slope of the perpendicular line is -1
We have a slope and a point
y = mx+b
y= -1x+b
Substitute the point into the equation
-3 = -1(5) +b
-3 =-5 +b
Add 5 to each side
-3+5 = b
2 =b
y = -x +2
EXAMPLE 10 Show that the points (a, a),(-a, - a) and (-3a, 3a) are the vertices of an equilateral triangle. Also find its area.
Answer:
The triangle is not equilateral.
Step-by-step explanation:
Distance formula:
[tex] d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} [/tex]
Distance from (a, a) to (-a, -a):
[tex] d_1 = \sqrt{(-a - a)^2 + (-a - a)^2} [/tex]
[tex] d_1 = \sqrt{(-2a)^2 + (-2a)^2} [/tex]
[tex] d_1 = \sqrt{8a^2} [/tex]
Distance from (-a, -a) to (-3a, 3a):
[tex] d_2 = \sqrt{(-3a - (-a))^2 + (3a - (-a))^2} [/tex]
[tex] d_2 = \sqrt{(-2a)^2 + (4a)^2} [/tex]
[tex] d_2 = \sqrt{20a^2} [/tex]
Distance from (-3a, 3a) to (a, a):
[tex]d_3 = \sqrt{(-3a - a)^2 + (3a - a)^2}[/tex]
[tex]d_3 = \sqrt{(-4a)^2 + (2a)^2}[/tex]
[tex]d_3 = \sqrt{20a^2}[/tex]
The three sides do not have the same length, so the triangle is not equilateral.
The distance between two points on a number line can be found by taking the ____A_____ of the ____B_____ of the coordinates. Fill in the blanks in the previous sentence by matching the letter for each blank with the correct answer.
Answer:
The distance between two points on a number line can be found by taking the absolute value of the difference of the coordinates.
Step-by-step explanation:
Every point can be paired with a number on a number lineThe coordinate is the number associated with a pointTo find the distance between point A and B you subtract the coordinates in any order you like and take the absolute value.what is the answer to x2 = 121.
Answer:
11 if you mean x^2
Step-by-step explanation:
Since we are solving for x, we need to just get x by its self. The only thing we have to do is get rid of the exponent of (^2). to do this, we have to take teh square root of both sides:
The square root of x^2 is x
The square root of 121 is 11
So the asnwer is x = 11
Step-by-step explanation: A common mistake in this problem would be to say that if x² = 121, x must equal 11.
However, you must set the equation equal to 0 first.
So our first step is to subtract 121 from both sides to get x² - 121 = 0.
Next, factor the left side to get (x + 11)(x - 11) = 0
So either x + 11 = 0 or x - 11 = 0.
Solving each equation from here, we find that x = -11 or x = 11.
So our answer is not just 11, it's {11, -11}.
24 is 75% percent of what number?
Answer:
32
Step-by-step explanation:
We can call the number x. 75% can be expressed as 0.75 so we can write the following equation: 0.75x = 24. Dividing both sides by 0.75 to get rid of the coefficient of x, we get that x = 32.
Answer:
32.
Step-by-step explanation:
Let's say the number we are trying to find is x.
24 = 0.75x
0.75x = 24
x = 24 / 0.75
x = 32
Hope this helps!
How many and of which kind of roots does the equation
f(x) = x5+ 3x4 + 8x3 + 14x2 + 16x + 8 have?
A. 2 real; 3 complex
B.5 real
C. 3 real;2 complex
D.1 real;4 complex
Answer:
D. 1 real; 4 complex
Step-by-step explanation:
1. Calculate the total number of roots
The fundamental theorem of algebra states that any polynomial of degree n has n roots.
Your polynomial is fifth degree, so it has five roots.
2. Calculate the number of real roots
We can use Descartes' rule of signs to determine the number of real roots:
The number of positive real roots is the same as the number of changes in the sign of the coefficients of ƒ(x) or less than by an even number.
The number of negative real roots is the same as the number of changes in sign of the coefficients of the terms of f(-x) or less than this by an even number.
(a) Number of positive real roots
The coefficients of ƒ(x) are
+1 +3 +8 +14 +16 + 8
There are no changes of sign, so there are no positive real roots.
(b) Number of negative real roots
(i) Find f(-x)
f(-x) = -x⁵+ 3x⁴ - 8x³ + 14x² - 16x + 8
(ii) Count the changes of sign
The coefficients of f(-x) are
-1 ∥ +3 ∥ -8 ∥+14 ∥ -16 ∥ +8
There are five changes of sign.
Thus, the number of negative roots is five, three, or one.
So far, we know that we have five roots. None is positive, and there could be one, three, or five negative real roots.
3. Confirm by sketching the graph
The real roots are the points at which the graph crosses or touches the x-axis.
The graph (see below) crosses the x-axis at only one point.
Thus. we have
one real root (negative) four complex roots
a police car drives a constant speed of 64 mph.how far can it travel in 2 hours
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Please answer this question now
Answer:
76 degrees.
Step-by-step explanation:
Let as consider O is the center of the circle . So from the figure it is clear that
[tex]\angle AOB=44^{\circ}[/tex]
[tex]\angle COD=118^{\circ}[/tex]
By central angle theorem, central angle subtended by an arc is twice of inscribed angle of the same arc.
We know that, [tex]\angle BAD=97^{\circ}[/tex] and angle BOD is the central angle subtended by arc BD.
[tex]\angle BOD=2\times \angle BAD[/tex]
[tex]\angle BOD=2\times 97^{\circ}[/tex]
[tex]\angle BOD=194^{\circ}[/tex]
Now,
[tex]\angle BOD=\angle BOC+\angle COD[/tex]
[tex]194^{\circ}=\angle BOC+118^{\circ}[/tex]
[tex]194^{\circ}-118^{\circ}=\angle BOC[/tex]
[tex]76^{\circ}=\angle BOC[/tex]
[tex]m(arc(BC))=76^{\circ}[/tex]
Therefore, the measure of arc BC is 76 degrees.
I need Help please answer :((
Answer:
Second option is the correct answer
[tex] {3}^{ - 4} [/tex]
Step-by-step explanation:
[tex] {3}^{ - 8} . {3}^{4} = {3}^{ - 8 + 4} = {3}^{ - 4} [/tex]
Answer:
The answer is D because you multiply the exponents so -8 times 4 is -32
Hope this helps and plz mark branliest!
Step-by-step explanation:
If a square has a side of length 3, then it’s area is 9. This square has a side of length 3, so it’s area is 9. Is it valid or invalid?
Answer:
Yes it is valid
Step-by-step explanation:
A square is a geometric shape which is also known as a Quadrilateral. This means that it has 4 sides.
For a square, it's 4 sides are equal to one another or we can put it in other words as the length of the 4 sides of a square are congruent to one another.
From the above question, we are asked that:
"If a square has a side length of 3, it's area is 9. Is it valid or invalid?"
The above statement is valid. This is because, the formula for the Area of a Square is given as
L × L = L²
Where L = Side length = 3
Area = 3 × 3 = 3²
Area = 9
Therefore, the statement is valid.
If JK = 28, JL = 20, KL = 13, and ML = 22, calculate NL. Image not set to scale.
Answer:
NL = 440 /13 or 33.85 (to two decimals)
Step-by-step explanation:
Consider triangles JKL and NML
angle JLK = angle NLM vertical angles
angle KJL = angle MNL given
Therefore triangles JKL and NML are similar
By proportion of corresponding sides of similar triangles,
NL / JL = LM / LK
Substitute given values
NL / 20 = 22 / 13
solve for NL
NL = 20*22 / 13 = 440 /13 or 33.85 (to two decimals)
Answer:
[tex]\huge \boxed{33.85}[/tex]
Step-by-step explanation:
JL is similar to NL. KL is similar to ML.
We can use ratios to solve.
JL/KL = NL/ML
Let the length of NL be x.
20/13 = x/22
Cross multiply.
13 × x = 22 × 20
13x = 440
Divide both sides by 13.
(13x)/13 =440/13
x = 440/13 = 33.846154...
A will states that 4/5 of estate is to be divided among relatives. Of the remaining estate1/4 goes to the American cancer society. What fraction of the estate goes to the American cancer Society
Answer:
1/9 of the estate is for American cancer societyStep-by-step explanation:
In this problem we are expected to calculate the fraction of a whole that belongs to a part. that is the fraction of the estate the belongs to American cancer society.
let us state as given that the total estate is 5
and 4 is to be divided among relatives, remaining 1
out of the remaining 1 estate,
1/4 belongs to American cancer society
Therefore the fraction of the 5 estates that belongs to American cancer society is = 1/4 of 1/5= 1/9
use the given information to find the new price
wholesale price: $35
markup: 95%
Answer:
i think the answer is either $68.25 or $110
i hope this helped
Dr. Green has to multiply the weight of the team's bug spray bottles, 7 x 90 grams. To solve this, he writes out the equation 7 x 9 x 10. Why does this strategy work?
Because 9 × 10 equals 90
Then 7×90=7×9×10
Write an equation in slope-intercept form for the line the road will follow. (The road is the dashed line.)
Answer:
x=6
Step-by-step explanation:
The crocodile river is y = 4
The road will intersect at ( 6,4)
We have two points on the line
(6,7) and (6,4)
The slope is
m = (y2-y1)/(x2-x1)
= (4-7)/ (6-6)
= -3/0
The slope is undefined
That means the equation is in the form
x=
Since the x coordinate is 6
x=6
A culture of bacterial triples in size every four hours. If the bacteria population is estimated to be three million now, what will it be one day from now?
A. 4,238,000,000
B. 6,561,000,000
C. 243,000,000
D. 2,187,000,000
Answer:
1 day = 24 hours
we cam divide in 6 periods of 4 hours
if bacteria triples in size every four hours
3 millions at begining
3^7 = 2'187'000'000 bacteria
Espero que te sirva
Answer: Geometric progression
Step-by-step explanation:
0h -> 3x10^6 /4h-> 9x10^6 / 8h-27x10^6 / 12h->81x10^6 / 16h->243x10^6 / 20h-> 729x10^6 / 24h->2187x10^6 = 2.187.000.000.:
7a - 3 = 3 - 2a What does a equal?
Answer:
2/3
Step-by-step explanation:
1) Move the 7a to the other side
2) Move the 3
3) Combine like terms
4) Divide by 9
5) Answer is 2/3
Answer:
a=2/3
Step-by-step explanation:
All this problem needs is some knowledge of how an = sign and basic equations work
7a-3=3-2a
7a+2a=3+3 (Sign becomes opposite on the other side of the equation)
9a=6
a=2/3
Thank you for your time!
which choice is the solution set for the inequality below
x < 3
Answer:
B) x < 9
Step-by-step explanation:
√x < 3
(√x)² > 3²
x < 9
reduce to simplest form -7/12+3/8 =_____
Answer:
-5/24
Step-by-step explanation:
make the denominators the same!
9. You run a business making birdhouses. You spend $600 to start your business, and it costs you $5.00
to make each birdhouse.
# of birdhouses
1
2
3
4
5
6
7
Total cost to build
Answer:
$635
Step-by-step explanation:
$5x7 birdhouses=$35want
So, $35+$600=$635 total!
I hope this helps you!
Multiplication is the process of multiplying. The cost of building 7 birdhouses will be $635.
What is multiplication?Multiplication is the process of multiplying, therefore, adding a number to itself for the number of times stated. For example, 3 × 4 means 3 is added to itself 4 times, and vice versa for the other number.
The cost of the birdhouse is the sum of the fixed cost, which is the setup cost of the business of $600, and the variable cost is the cost that is needed to make a single house, therefore, $5.
Now, the total cost of making n number of houses will be,
Cost of making n house = Fixed cost + variable cost
= $600 + $5(n)
Further, the table can be filled using the above formula by substituting the value of n for the number of houses. Therefore,
Number of bird houses Total cost to build
1 $600+$5(1) = $605
2 $600+$5(2) = $610
3 $600+$5(3) = $615
4 $600+$5(4) = $620
5 $600+$5(5) = $625
6 $600+$5(6) = $630
7 $600+$5(7) = $635
Hence, the cost of building 7 birdhouses will be $635.
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simplfy given equation using the distributive property 6 - (3x+10) + 4(2 - x) =15
Answer:
see below
Step-by-step explanation:
6 - (3x+10) + 4(2 - x) =15
Distribute
6 - 3x -10 +8 -4x = 15
Combine like terms
4 -7x = 15
Subtract 4 from each side
4 -7x-4 =15-4
-7x =11
Divide each side by -7
-7x/-7 = 11/-7
x = -11/7
In Isosceles trapezoid ABCD, the longer base, AB, is one and one half times as long as the shorter base, CD. The other two sides, AD and BC, are both 13 cm. long. a. If the perimeter is 76 cm. find the lengths of AB and CD. b. If the height of the trapezoid is 12 cm. find its area. (Hint: Area
otal perimeter = 76cm = AB + BC + CD + AD
AD & BC = 13cm
AB = 1.5*(CD)
Solution:
Since we know AD & BC are both 13cm long, plug those numbers into the perimeter equation
76cm+=+AB+%2B+BC+%2B+CD+%2B+AD Place 13cm in for AD & BC
76cm+=+AB+%2B+13cm+%2B+CD+%2B+13cm Combine like terms
76cm+=+AB+%2B+CD+%2B+26cmSubtract 26cm from both sides
50cm+=+AB+%2B+CD Now it is time to substitute the 1.5*(CD) for AB
50cm+=+1.5%2A%28CD%29+%2B+CD rewrite the equation
50cm+=+2.5%2A%28CD%29 Divide both sides by 2.5
20cm+=+CD
To find AB, plug 20cm in for CD in the equation AB = 1.5*(CD)
AB+=+1.5%2A20cm
AB+=+30cm
How to do this question plz answer me step by step plzz plz
Answer:
194.25meters
Step-by-step explanation:
The distance around the running track is calculated as:
Perimeter of the first semi circle + Perimeter of the second circle +50m + 50m
Semi circle has a length or diameter of = 30m
r = 30/2 = 15m
Perimeter of a circle = 2πr
Hence for a semi circle = 2πr/2 = πr
Perimeter of the first semi circle = π × 15
= 47.123889804m
Perimeter of the second semi circle is the same hence,
π × 15 = 47.123889804m
The distance around the running track
= 47.123889804m + 47.123889804m + 50m + 50m
= 194.24777961m
Approximately= 194.25meters.
Given the two figures are similar, calculate the value of y
Answer:
y+1/12.5=2/5
or,5y+5=25
ory=20/5
so, y=4
Step-by-step explanation:
hope it helps you
Can any kind soul help me please
Use the cosine rule
Answer:
M = 45°
Step-by-step explanation:
a²=b²+c²-2bc Cos A
m² = n² + p² - 2np cos M
(5.1)² = (7.2)² + (5.3)² - 2(7.2)(5.3) cos M
26.01 = 51.84 + 28.09 - 76.32 cos M
-53.92 = -76.32 cos M
0.7065 = cos M
M = [tex]cos^{-1 }[/tex](0.7065)
M = 45°
The length of a rectangle is represented by the function L(x) = 4x. The width of that same rectangle is represented by the function W(x) = 7x2 − 4x + 2. Which of the following shows the area of the rectangle in terms of x? (L + W)(x) = 7x2 + 2 (L + W)(x) = 7x2 − 8x + 2 (L • W)(x) = 28x3 − 16x2 + 8x (L • W)(x) = 28x3 − 4x + 2
Answer:
(L ⋅ W)(x) = 28x3 − 16x2 + 8x
Step-by-step explanation:
I took the test hope it helps :3
The area of the rectangle is (L · W) (x) = 28x³ - 16x² + 8x. Thus, the correct option is C.
What is an area?The area of a 2D form is the amount of space within its perimeter. It is measured in square units such as cm², m², and so on. To find the area of a square formula or another quadrilateral, multiply its length by its width.
Given the length of the rectangle is L(x)=4x, and the width is W(x)=7x²-4x+2. Therefore, the area of the rectangle in terms of x is,
L(x)×W(x) = 4x × (7x²-4x+2)
(L · W) (x) = 28x³ - 16x² + 8x
Hence, the area of the rectangle is (L · W) (x) = 28x³ - 16x² + 8x. Thus, the correct option is C.
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please help !!! idk how to do this
Answer:
C
Step-by-step explanation:
Here, we want to state the interval that has the highest frequency.
What we are asked here is the range of values where we have the the most common salary.
For 0-10, we have 1 ( Estonia)
For 11-20, we have 1 (Israel)
For 21-30 , we have 0
For 31-40, we have 1 ( Greece)
For 41-50, we have 5
For 51-60, we have 3
For 61-70, we have 1 (Luxembourg)
So 41-50 is the class with the highest frequency
I need hellp please its my last chance to become a senior please someone
Answer:
d= 6
r= 6/2
r=3
V= π. r². h
V= π . 3². 14
V= π. 9 . 14
V= π 126 cm³
V= 126 π cm³ (π not in number)
hope it helps^°^
Answer:if you use the formula it is 126 pi cm cubed
The answer is c
Step-by-step explanation:
write as an expression: a number that is equal to five less than b
Answer:
[tex]\huge\boxed{a = b-5}[/tex]
Step-by-step explanation:
Let the number be a
So, the given condition is:
a = b-5
Answer:
[tex]\Huge \boxed{a=b-5}[/tex]
Step-by-step explanation:
Let the number be [tex]a[/tex].
[tex]a[/tex] is equal to 5 less than [tex]b[/tex].
5 is subtracted from [tex]b[/tex].
If y=26−(3x+2), then x = ?
Answer:
-1/3y +8 = x
Step-by-step explanation:
y=26−(3x+2)
Distribute
y = 26 -3x-2
Combine like terms
y = 24 -3x
Subtract 24 from each side
y -24 = -3x
Divide each side by -3
y / -3 -24/-3 = -3x/-3
-1/3y +8 = x
