Answers
We have
(a + bx) / (a - bx) = (b + cx) / (b - cx)
==> (a + bx) (b - cx) = (a - bx) (b + cx)
==> ab + (b ² - ac) x - bcx ² = ab + (ac - b ²) x - bcx ²
==> (b ² - ac) x = (ac - b ²) x
==> b ² - ac = ac - b ²
==> 2b ² = 2ac
==> b ² = ac … … … [1]
Similarly, you would find
(a + bx) / (a - bx) = (c + dx) / (c - dx)
==> ad = bc … … … [2]
and
(b + cx) / (b - cx) = (c + dx) / (c - dx)
==> c ² = bd … … … [3]
Now:
c ² = bd ==> b = c ² / d
b ² = ac ==> c = b ² / a
ad = bc ==> d = bc / a
and we find
d / c = (bc / a) / (b ² / a) = c / b
and
c / b = (b ² / a) / (c ² / d) = (b ² d) / (a c ²) = b / a
which is to say, the ratio between d and c is equal to the ratio between c and b, and also equal to the ratio between b and a. Therefore (a, b, c, d) are in a geometric progression.
Related Questions
1. Determine the sum of the first 53 terms of the following series: 179+173+167+...
2. Determine the sum of the first 19 terms of the following series: 6−12+24−48+...
Answers
(1) This series consists of terms of an arithmetic sequence:
179 - 173 = 6
173 - 167 = 6
and so on, so that the n-th term in the series is (for n ≥ 1)
a(n) = 179 - 6 (n - 1) = 185 - 6n
Then the sum of the first 53 terms is
[tex]\displaystyle\sum_{n=1}^{53}(185-6n) = 185\sum_{n=1}^{53}1-6\sum_{n=1}^{53}n[/tex]
[tex]\displaystyle\sum_{n=1}^{53}(185-6n) = 185\times53-6\times\frac{53\times54}2[/tex]
[tex]\displaystyle\sum_{n=1}^{53}(185-6n) = \boxed{1219}[/tex]
(2) This series has terms from a geometric sequence:
-12 / 6 = -2
24/(-12) = -2
-48/24 = -2
and so on. The n-th term is (again, for n ≥ 1)
a(n) = 6 (-2)ⁿ⁻¹
and the sum of the first 19 terms is
[tex]\displaystyle\sum_{n=1}^{19}6(-2)^{n-1} = 6\left(1 + (-2) + (-2)^2 + (-2)^3 + \cdots+(-2)^{19}\right)[/tex]
Multiply both sides by -2 :
[tex]\displaystyle-2\sum_{n=1}^{19}6(-2)^{n-1} = 6\left((-2) + (-2)^2 + (-2)^3 + (-2)^4 + \cdots+(-2)^{20}\right)[/tex]
Subtracting this from the first sum gives
[tex]\displaystyle(1-(-2))\sum_{n=1}^{19}6(-2)^{n-1} = 6\left(1 -(-2)^{20}\right)[/tex]
and solving for the sum, you get
[tex]\displaystyle3\sum_{n=1}^{19}6(-2)^{n-1} = 6\left(1 -(-2)^{20}\right)[/tex]
[tex]\displaystyle\sum_{n=1}^{19}6(-2)^{n-1} = 2\left(1 -(-2)^{20}\right)[/tex]
[tex]\displaystyle\sum_{n=1}^{19}6(-2)^{n-1} = 2\left(1 -(-1)^{20}2^{20}\right)[/tex]
[tex]\displaystyle\sum_{n=1}^{19}6(-2)^{n-1} = 2\left(1 -2^{20}\right) = 2-2^{21} = \boxed{-2,097,150}[/tex]
pls help i need both blanks the options for the second one is left, right, up, down PLS HURRY ITS TIMED!!
Answers
Answer:
The graph is shifted 7 units right and 5 units up.
find the mean of the following 2x-5y,5x+2y,8x+6y,x-y
Answers
Answer: 4x + 0.5y
Step-by-step explanation:
Concept:
Here, we need to understand the idea of the mean (average).
The "mean" is the "average" you're used to, where you add up all the numbers and then divide by the number of numbers.
If you are still confused, please refer to the attachment below for a graphical explanation.
Solve:
**Disclaimer** I assume the question is asking for the arithmetic mean instead of geometric. If it was, then you can refer to my answers. If it was not, then you can point it out and I will redo the question.
Terms: 2x-5y, 5x+2y, 8x+6y, x-y
Number of terms: 4
[(2x-5y) + (5x+2y) + (8x+6y) + (x-y)] / 4
=[2x + 5x + 8x + x + 2y - 5y + 6y - y] / 4
=[16x + 2y] / 4
=4x + 0.5y
Hope this helps!! :)
Please let me know if you have any questions
In △MNP , point Q is between points M and N, and point R is between points N and P. Point H is the incenter of the triangle, HQ⊥MN, and HR ⊥NP. QN=36 and HN=39 . What is HR ? Enter your answer in the box.
Answers
Answer:
15
Step-by-step explanation:
The given parameters are represented by drawing the triangle with the details given using MS Visio
The point Q is located between points M and N in ΔMNP
The point R is located between points N and P in ΔMNP
The incenter of the triangle = H
Line HQ is perpendicular to side MN on ΔMNP
Line HR is perpendicular to side NP on ΔMNP
The length of the segment QN = 36
The length of the segment HN = 39
By Pythagoras' theorem, HQ = √((HN)² - (QN)²)
∴ HQ = √(39² - 36²) = 15
HQ = 15
Given that H is the incenter of ΔMNP, the lengths of the perpendicular from H to the sides of the triangle are equal to the radius of the inscribed circle of the triangle
Therefore, the radius lengths are HQ, and HR
∴ HR = HQ = 15
HR = 15.
pls help w work!!
The equation P=2(L + W) is used to find the
perimeter, P, of a rectangle based on the length, L,
and Width, W. Which of the following correctly expresses the value of the width?
(a) P - 2L
(b) P - 2L / 2
(c) 2L - P / 2
(d) 1/2 (P-L)
Answers
Lets Do
[tex]\\ \sf\longmapsto p = 2(l + w) \\ \\ \sf\longmapsto l + w = \frac{p}{2} \\ \\ \sf\longmapsto w = \frac{p}{2} - l \\ \\ \sf\longmapsto \boxed{ \bf \: w = \frac{p - 2l}{2} }[/tex]
Find the product. (-2x^2)^3 ·3x
Answers
Answer:
-24 x^7
Step-by-step explanation:
(-2x^2)^3 ·3x
(-2x^2) (-2x^2) (-2x^2)*3x
-8 x^6 *3x
-24 x^7
Tìm x, y sao cho: B=-x^2+2xy-4y^2+2x+10y-8
Answers
Answer:
Hello,
Step-by-step explanation:
All i can do is to show you the ellipse.
b. Compare the similar triangle proof from question 3 with the inscribed square
proof. How are they different? Which method was easier for you to understand?
(1 point)
Answers
Answer:
i might be wrong but this is what i put
Step-by-step explanation:
In question 3 it was comparing three triangles where now it is using the triangles to find the area of a square instead of proving that they are the same.
On a Job application Doris gave her age as 32 years. Her actual age at the time was about 27. What is the relative error fo her age?
Answers
Answer:
Relative error = 0.19
Step-by-step explanation:
From the question given above, the following data were obtained:
Measured age = 32 years
Actual age = 27 years
Relative error =?
Next, we shall determine the absolute error. This can be obtained as follow:
Measured age = 32 years
Actual age = 27 years
Absolute error =?
Absolute error = | Measured – Actual |
Absolute error = | 32 – 27 |
Absolute error = 5 years
Finally, we shall determine the relative error. This can be obtained as follow:
Absolute error = 5 years
Actual age = 27 years
Relative error =?
Relative error = Absolute error / Actual years
Relative error = 5 / 27
Relative error = 0.19
Mrs. Kennedy is teaching an 8th grade class. She is standing 7 meters in front of Catherine. Davis is sitting to Catherine’s left. If Davis and Mrs. Kennedy are 12 meters apart, how far apart are Davis and Catherine?
13.90 meters
5 meters
9.75 meters
4.36 meters
Answers
Answer:
9.75 meters
Step-by-step explanation:
Davis and Catherine are approximately 13.90 meters apart.
How to determine distance apartTo find the distance between Davis and Catherine, we can use the concept of right triangles and apply the Pythagorean theorem.
Let's consider a right triangle where the distance between Davis and Mrs. Kennedy is the base, the distance between Mrs. Kennedy and Catherine is the height, and the distance between Davis and Catherine is the hypotenuse.
According to the given information, Mrs. Kennedy is 7 meters in front of Catherine, and Davis and Mrs. Kennedy are 12 meters apart.
Using the Pythagorean theorem, we have:
(Base)² + (Height)² = (Hypotenuse)²
Substituting the given values:
(12)² + (7)² = (Hypotenuse)²
Simplifying the equation:
144 + 49 = (Hypotenuse)²
193 = (Hypotenuse)²
Taking the square root of both sides:
√193 ≈ 13.89 = 13.90
Therefore, Davis and Catherine are approximately 13.90 meters apart.
Learn more about distance at
https://brainly.com/question/26550516
#SPJ2
Two towns A and B are 220km apart. A bus left town A at 11.00 AM and travelled towards town B at 60km/hr. At the same time, a van left town B for town A and travelled at 80km/hr. The van stopped for a total of 45 minutes on the way before meeting the bus. Calculate the distance covered by the bus before meeting the van. Please show clear working and explanation to get a brainlist !!!
Answers
Answer:
Sa / Va = time traveled by bus a
Sb / Vb + 3/4 = time traveled by van b
Sa / Va = Sb / Vb + 3/4 times traveled are the same
= (220 - Sa) / Vb + 3/4
Sa ( 1 / Va + 1 / Vb) = 220 / 80 + 3/4
Sa (140 / 4800) = 3.5
Sa = 120 km
Check: 120 km / 60 km/hr = 2 hr = Ta
Sb = 1.25 * 80 = 100 km traveling for 1.25 hrs
Four cans of cat food and 3 cans of dog food cost $1.99. Four cans of the same cat food and 1 can of the same dog food cost $1.33 hat is the cost of one can of cat food
Answers
Answer:
$0.25
Step-by-step explanation:
We can use System of Equations to find out how much a can of cat food costs.
Let's use variables to represent the cat food and dog food:
x = cost of 1 cat food can
y = cost of 1 dog food can
Here are our 2 equations based on the scenarios in the question:
4x + 3y = 1.99
4x + y = 1.33
Now let's set the second equation to y using basic algebra:
4x + y = 1.33
y = -4x+1.33
And we're going to plug that value of y, which is -4x+1.33 into the first equation and solve:
4x + 3y = 1.99
4x + 3(-4x+1.33) = 1.99
4x + -12x+3.99 = 1.99
-8x + 3.99 = 1.99
-8x = -2
x = 1/4
x = 0.25
1 can of cat food costs $0.25
Hope that helps (●'◡'●)
Answer:
.25
Step-by-step explanation:
set up equations
1)4c+3d=1.99
2)4c+d=1.33
Method of use:Elimination
4c+3d=1.99
- (4c+d)=-(1.33)
___________
=2d=.66
divide by two on both sides to get .33 for d.
plug in
4c+.33=1.33
subtract .33 on both sides
4c=1
divide by four on both sides to get c
c=1/4 or .25
What is the slope of the line passing through the points
(-3, - 5) and (-1,6)? (URGENT)
Answers
Hope your day is going well
Slope equation is y2-y1/x2-x1
Y2= 6
Y1= -5
X2 = -1
X1 = -3
6 - -5/ -1 - -3
11/2 is the fraction
Decimal form 0.18
Hope this helps *smiles*
Sorry if this is wrong
1)The sum of two consecutive multiples of 5 is55. Find these multiples.
2)The sum of three consecutive integers is 93. What are the integers?
3)If five is subtracted from three times a number, the result is 10. What is the number?
Answers
Part 1
Let the consecutive multiples be 5x and 5x + 5
ATQ
5x + 5x + 5 = 55
10x = 55 - 5
10x = 50
x = 5
Answer is 25 and 30
Part 2
Let the number be x , x + 1, x + 2
ATQ
x + x + 1 + x + 2 = 93
3x + 3 = 93
3x = 93 - 3
x = 90/3
x = 30
The integers are 30,31 and 32
Part 3
Let the number be x
ATQ
3x - 5 = 10
3x = 10 + 5
x = 15/3
x = 5
The number is 5
Answered by Gauthmath must click thanks and mark brainliest
Please help!!!!!!!!!!!!!!
Answers
Answer:
7^-22
Step-by-step explanation:
Exponent laws.
What is the perimeter of this parallelogram? Please help asap!
Answers
18 units
Step-by-step explanation:
a^2 + b^2 = c^2
3^2 + 4^2 = c^2
9 + 16 = c^2
c^2 = 25
Square root of 25 = 5
5 + 5 = 10
(Opposite sides are congruent)
4 + 4 = 8
10 + 8 = 18
Therefore, the perimeter is 18
This Venn diagram shows the pizza topping preferences for 9 students.
What elements are in A and B?
(Look at picture)
Answers
Answer:
I think the answer is C.
SOMONEEeeeee HELPP MEEE OUTTTT!!!
Answers
Answer:
simple 49+44=93 then you do 180 is the angle of a straight line so we do 180-93=87
NEED THIS ASAP :)
What is the length of the y-component of the vector plotted below?
A. 3
B. 4
C. 1
D. 2
Answers
Answer:
4
Step-by-step explanation:
Length of the y component is how far the vector reaches vertically, so in this case it's 4
what is the value of a if va- vh is equals to 1
Answers
Answer:
[tex] \displaystyle a = \frac{1+vh}{v}[/tex]
Step-by-step explanation:
we want to figure out a value of a for the following condition
[tex] \displaystyle va - vh = 1[/tex]
to do so factor out v;
[tex] \displaystyle v (a - h )= 1[/tex]
divide both sides by v which yields:
[tex] \displaystyle \frac{(a-h) \cancel{(v)}}{ \cancel{v}}= \frac{1}{v} [/tex]
therefore,
[tex] \displaystyle a-h = { \frac{1}{v}}[/tex]
now,add h to both sides:
[tex] \displaystyle a = \frac{1}{v}+h[/tex]
further simplification if necessary:
[tex] \displaystyle a =\boxed{ \frac{1+vh}{v}}[/tex]
factor out of v
[tex]\sf{v(a-h)=1 }[/tex]Dividing both sides by (v)
[tex]\sf{\dfrac{v(a-h)}{(v)}=\dfrac{1}{(v)} }[/tex]cancel out (v)
[tex]\sf{\dfrac{\cancel{v}(a-h)}{\cancel{(v)}}=\dfrac{1}{(v)} }[/tex][tex]\sf{ a-h=\dfrac{1}{v} }[/tex]
add h in both sides
[tex]\sf{a-h+h=\dfrac{1}{v}+h }[/tex]cancelout h
[tex]\sf{a-\cancel{h}+\cancel{h}=\dfrac{1}{v}+h }[/tex] [tex]\sf{a=\dfrac{1}{v}+h }[/tex] [tex]\boxed{\sf{a=\dfrac{1+vh}{v} } }[/tex][tex]\sf{ }[/tex] [tex]\sf{ }[/tex]
Therefore:-the value of a if va- vh is equals to 1 is [tex]\bold{\dfrac{1+vh}{v} }[/tex]
What is the explicit formula for this sequence?
-9, -3, 3, 9, 15,
Answers
Answer:
+6
Step-by-step explanation:Look at the trend of numbers and notice. Maybe put it in a table.
i need help. i don't understand this at all.
Answers
Answer:
Step-by-step explanation:
If this is in terms of angles, 4x+6 must be equal to 90 since it is half of the angle produced by a line (180°) So solving for 4x+6=90, x=21
Diagram shows triangle ABC.
Workout the size of angles x,y,z
x= 70*
y= 30*
z= *
Answers
A triangle is equal to 180 degrees so 70+90=160
180-160=20
find sine of angle of inclination to the axis is of line y=1/3x√3+3
Answers
Answer:
1/2.
Step-by-step explanation:
The inclination of the line to the x axis = 1/3*√3
= √3/3.
This is the tangent of the angle.
The sine of the angle =√3/hypotenuse.
The hypotenuse = √( √3)^2 + 3^2) (By the Pythagoras theorem)
= √12
= 2√3
Therefore the required sine is √3/ 2√3
= 1/2.
I think that's what you want!!
please! can somebody help me?
Answers
Step-by-step explanation:
The depth of the water is increasing by 2 feet each minute.
In order for the parallelogram to be a rhombus, x=?
Answers
Answer:
Step-by-step explanation:
The diagonal must be an angle bisector for a rhombus.
That means that both bisected angles are equal.
2x + 16 = 5x - 8 Add 8 to both sides
2x + 16 + 8 = 5x
2x + 24 = 5x Subtract 2x from both sides
24 = 5x - 2x
24 = 3x Divide by 3
24/3 = x
x = 8
Determine which equations have the same solution set as StartFraction 2 Over 3 EndFraction minus x plus StartFraction 1 Over 6 EndFraction equals 6 x. – x + = 6x by recognizing properties, rather than solving. Check all that apply.
Answers
Answer:
A, B, F
Step-by-step explanation:
2/3 - x + 1/6 = 6x
Collect like terms
2/3 + 1/6 = 6x + x
(4+1) / 6 = 7x
5/6 = 7x
x = 5/6 ÷ 7
= 5/6 × 1/7
x = 5/42
a) 4 - 6x + 1 = 36x
4 + 1 = 36x + 6x
5 = 42x
x = 5/42
Equivalent to the last step of the simplification above
b) 5/6 - x = 6x
5/6 = 6x + x
5/6 = 7x
This is equivalent to the third step of the simplification
c) 4 - x + 1 = 6x
4 + 1 = 6x + x
5 = 7x
x = 5/7
Not equivalent to any of the steps in the simplification above
d) 5/6 + x = 6x
5/6 = 6x - x
5/6 = 5x
x = 5/6 ÷ 5
= 5/6 × 1/5
x = 5/30
Not equivalent to any of the steps in the simplification above
e) 5 = 30x
x = 5/30
Not equivalent to any of the steps in the simplification above
f) 5 = 42x
x = 5/42
Equivalent to the last step of the simplification above
What point lies on the line with point slope equation y-3=4(x+7)?
Answers
Answer:
(-7, 3)
General Formulas and Concepts:
Algebra I
Point-Slope Form: y - y₁ = m(x - x₁)
x₁ - x coordinate y₁ - y coordinate m - slopeStep-by-step explanation:
Step 1: Define
Identify
y - 3 = 4(x + 7)
↓ Compare to Point-Slope Form
Point (-7, 3)
Slope m = 4
Jada worked at the bakery for 14 hours last week he spent $12 of his earnings on a cake for his father‘s birthday as he was last with $86 after buying the cake what is Gianna‘s hourly wage
Answers
Answer:
$7 is his Hourly Wage.
Step-by-step explanation:
We can start by finding out how much money Jada started with by adding the amount of money he had after buying the cake with how much he spent on the cake, 86 + 12 = 98.
We now know how much money he had before buying anything. Now we can just divide the total amount of money by how long he worked.
98 ÷ 14 = 7
Solve for x. Round to the nearest tenth of a degree, if necessary. Please HELP!
Answers
Answer:
x = 29.5
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
cos x = adj side/ hypotenuse
cos x = 67/77
Taking the inverse cos of each side
cos^-1( cos x) = cos^-1 (67/77)
x = 29.52626525
To the nearest tenth
x = 29.5
