Monday
May 30, 2016

Posts by Reiny

Total # Posts: 34,826

Math
prob(good) = .9 prob(bad) = .1 you want prob(6 of 7 to be good) = C(7,6)(.9)^6 (.1) = .. you push the buttons
March 5, 2016

Math
value of $1.00 at end of 1 year: Bank A : amount = (1 +.0479/12)^12 = ... Bank B : amount = (1 + .048/4)^4 = .. compare the results
March 5, 2016

Algebra
are we solving √(8-3x) + √(6x-1) = 7 - 2√(9x-24) ???? I tested it in Wolfram, and there is no "real" solution, so I won't even try. http://www.wolframalpha.com/input/?i=%E2%88%9A(8-3x)+%2B+%E2%88%9A(6x-1)+%3D+7+-+2%E2%88%9A(9x-24) notice that ...
March 5, 2016

math
factors of 1440 2x720 3x480 4x360 5x288 6x240 8x180 9x160 10x144 12x120 15x96 16x90 18x80 20x72 24x60 30x48 32x45 36x40 ---> that's all of them values of n^2-1 1,3,8,15,24,35,48,63,80,99,120,143,168,195,288,325,360,399,440,483,529,575,624,675,728 the largest of these ...
March 5, 2016

math
values of n+1 2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,.... multiples of 4n+1 5,9,13,17,21,25,29,33,37,41,45,49,53,57,61,65,69,73,77,81,85,89,93,97,101,... let 4n+1) = k(n+1) k = (4n+1)/(n+1) , so k has to be whole number if n=2 , 9/3 = 3 --> k = 3 if n=3, 13/4 ≠ ...
March 5, 2016

Algebra
speed of slower --- x km/h speed of faster ---- x+2 km/h 20/x - 20/(x+2) = 20/60 = 1/3 times 3x(x+2) , the LCD 60(x+2) - 60x = x(x+2) x^2 + 2x - 120 = 0 (x+12)(x-10) = 0 x = 10 or x = -12, the ladder is silly The slower one went 10 km/h, and the faster went 12 km/h check: 20/...
March 5, 2016

Math
width --- x length --- (6/5)x (6/5)x^2 = 480 x^2 = 400 x = √400 = 20 picture is 20 inches by 24 inches
March 5, 2016

business math
Did you mean simple interest? if so, PRT = I 52600(.05)T = 1261 T = 1261/(.05(52600)) = .4795 years or 175 days check: 52600(.05)(175/365) = 1260.96 or $1261
March 5, 2016

Calc Derivatives
you should say y = (4x-3)/(3x^(1/2)) or f(x) = (4x-3)/(3x^(1/2)) dy/dx =[ 3x^(1/2) (4) - (4x-3)(3/2)x^(-1/2) ]/(9x) = 0 for a max/min 12x^(1/2) = (3/2)(4x-3)/x^(1/2) 12x = (3/2)(4x - 3) 24x = 12x - 9 12x=-9 x = -3/4 , but x ≥0 or else x^(1/2) is undefined. There are no ...
March 5, 2016

math ples help
using these log rules: log(ab) = loga + logb log(a/b) = loga - logb log( a^n) = nloga Rewrite 2log8/6 + 2^2log3 - 2log12 as log(64/36) + 4log3 - log144 = log(64/36) + log81 - log144 = log ( (64/36)(81)/144) = log 1 = 0
March 5, 2016

Math
The simple proportion for your similar triangles: h/48 = 5/12 12h = 240 h = 20 or by straight logic: The mirror is 4 times the distance away from the pole as she is from the mirror. So the flage pole is 4 times her height, or 20 ft " Find the geometric mean of the pair of...
March 5, 2016

math
Ok ... RS = sinx/√(1+cosx) * √(1-cosx)/√(1-cosx) , you did that = sinx √(1-cosx) /(√( (1+cox)(1-cosx) ) = sinx √(1-cosx)/√(1 - cos^2 x) = sinx √(1-cosx)/√sin^2 x = sinx √(1-cosx)/sinx = √(1-cosx) = LS
March 5, 2016

math
solve for m, the number of miles .09m + 57.98 = .14m + 49.98 9m + 5798 = 14m + 4998 ...
March 5, 2016

Math
Make a Venn diagram Label it P and B, for pepperoni and banana put 5 in the intersection of both circles - of the 25 who like pepperoni, 5 are already counted, so put 20 in the P circle apart from the intersection. - of the 31 who like banana peppers, 5 are already counted, so...
March 5, 2016

Maxima, Stationary Points
If (9*x^6+28*x^4+51*x^2-88*x-10)/(3*x^2+2)^2 is the derivative of some function and you want to find max/min, you would set the above equal to zero that would leave you with 9x^6 + 28x^4 + 51x^2 - 88x - 10 = 0 I am not at all familiar with your software, but my favourite math ...
March 5, 2016

math
How good are you at sketching 3-D diagrams? I let P be the point directly below plane A, and I now have 4 triangles, each in their own plane. Redraw each with a side view: right-triangle ABP , right angle at P right-triangle ACP, right angle at P triangle BCP , (on ocean floor...
March 5, 2016

trigonometry
sinx/secx = 1/tanx+cotx , is not true but sinx/secx = 1/(tanx+cotx) is true LS = sinx(1/cosx) =sinxcosx RS = 1/(sinx/cosx + cosx/sinx) = 1/( (sin^2 x + cos^2 x)/(sinxcosx) ) = 1/(1/sinxcosx)) = sinxcosx = LS
March 5, 2016

college algebra
let the three numbers be x x+2 x+4 2x - (x+2) = 20 x = 22 largest is x+4 = 26
March 5, 2016

MATH
Make a sketch, (it won't be to scale!) You will have an isosceles triangle with an angle at the earth of 31 minutes of angle. Draw in a perpendicular which would be 360,000 km If the radius of the moon is r, I see it as tan (0°15'30") = r/360000 r = 360000(tan...
March 5, 2016

Math
let the two numbers be 3x and 4x 3x+10 = 4x - 10 solve for x
March 5, 2016

Allgebra
let the two numbers be x and y (x+y)/2 = 17 x+y = 34 --> y = 34-x √(xy) = 8 xy=64 x(34-x) = 64 x^2 - 34x = -64 x^2 - 34x + 289 = 289-64 ---> I completed the square (x-17)^2 = 225 x-17 = ±15 x = 32 or x = 2 if x = 32, y = 2 if x = 2, y = 32 , (called ...
March 5, 2016

Algebra
in a harmonic progression, the reciprocals of its terms form an arithmetic progression. so if the third term of the HP is x then 1/a , 1/b, and 1/x form an AP that is, 1/b - 1/a = 1/x - 1/b 2/b - 1/a = 1/x (2a - b)/(ab) = 1/x x = ab/(2a - b)
March 5, 2016

Algebra
"one third of a one third of a point is deducted" - why not just say say: " 1/9 of a point is deducted for an incorrecte answer" ?? number correct --- x number incorrect --- 72-x x - (1/9)(72-x) ≥ 60 x - 8 + (1/9)x ≥ 60 (10/9)x ≥ 68 x &#...
March 4, 2016

maths
1/x + 1/(x+6) = 1/(40/3) = 3/40 times 40x(x+6) 40(x+6) + 40x = 3x(x+6) 3x^2 - 62x - 240 = 0 t = (62 ± √6724)/6 = 24 or -3/1/3 , but x > 0 so x = 24 tom alone can do it in 24 hrs, John alone can do it in 30 hours check: at combined time, time of job = 1/(1/24+1/...
March 4, 2016

probability
prob(zero people leave tip) = C(6,0)(.7)^0 (.3)^6 = .000729 prob(1 person leaves tip) = C(6,1)(.7)(.3)^5 = .010206 prob(2 persons leave tip) = C(6,2)(.7)^2 (.3)^4 = .059535 prob(3 persons leave tip) = C(6,3)(.7)^3 (.3)^3 = .18522 prob(4 people leave tip) = C(6,4)(.7)^4 (.3)^2...
March 4, 2016

Calculus with Analytical Geometry
you are looking for the vertex of h = -16t^2 + 1000t + 20 the t of the vertex is -1000/-32 = 31.25 seconds for that value of t, h = 15645 ft
March 4, 2016

Math Algebra Intermediate
ay - a^6 y^6 = ay(1 - a^5 y^5) Much Ado About Nothing, as Shakespeare would say.
March 4, 2016

Math
i = .042/12 = .0035 n = 30(12) = 360 PV =.8(260000) = 208,000 let the payment be P P( 1 - 1.0035^-360)/.0035 = 208000 P = $1017.16
March 4, 2016

Math
S(1) = 2 by the formula: S(1) = 1(1 + 3)/2 = 2 S(2) = 2+5 = 7 by the formula: S(2) = 2(1+6)/2 = 7 S(3) = 2+5+8 = 15 by formula: S(3) = 3(1+9)/2 = 15 seems to work.
March 4, 2016

math
let the two numbers be x and x+1 4x + x(x+1) = 36 x^2 + 5x - 36 = 0 (x+9)(x-4) = 0 x = 4 or x = -9, but x>0 x = 4 the two numbers are 4 and 5
March 4, 2016

Algebra 2
(log5 16^3 )(log11 6^2 = log x 3(log16/log5)(2)(log6/log11) = logx 6(log16/log5)(log6/log11) 6(1.28724...) = logx 7.72346... x = 10^7.72346.. x = appr 52,900,679 I was using the log properties: log a^n = n loga , and log a b = logb/loga
March 4, 2016

algebra 1b
typo: don't know where my 20 came from. should have been: quarters ---- x nickels ----- 16-x solve for x: 25x + 5(16-x) = 220
March 4, 2016

algebra 1b
quarters ---- x nickels ----- 20-x solve for x: 25x + 5(20-x) = 220
March 4, 2016

math
let the total be x make a Venn diagram of two intersecting circles, and place 27 in the intersection. In the exclusive parts of the two circles place (3/4)x - 27 and (4/7)x - 27 then: (3/4)x-27 + 27 + (4/7)x-27 = x (3/4)x + (4/7)x-27 = x multiply each term by 28, the LCD 21x...
March 4, 2016

Math
Was that supposed to say KL = 14 ? I will assume that, since N does not enter the picture elsewhere. Let's find angle K, the largest angle. 18^2 = 14^2 + 16^2 - 2(14)(16)cosK 448cosK = 128 cosK = 2/7 K = appr 73.4° area = (1/2)(14)(16)sinK = 112(.9583..) = appr 107.33 ...
March 3, 2016

Geometry
in any rhombus, the diagonals right-bisect each other. illustration: midpoint of PR = (0,0) midpoint of QS = (0,1/2) oops, something is not right the figure is not a rhombus, I think S should be (1,-2) then midpoint of QS is also (0,0) and the two diagonals would bisect each ...
March 3, 2016

typo at end - statistics
Last line of previous post should have been: number of ways = 4x36 = 144
March 3, 2016

statistics
a) consider each couple as one unit, so you are just arranging 3 units. Number of ways = 3! = 6 b) I don't understand the question c) for the men to sit together, we could have MMMWWW **** WMMMWW WWMMMW WWWMMM Number of ways to do *** = 3x2x1x3x2x1=36 but each of the other...
March 3, 2016

Calculus Related Rates
let the distance between them be x ft after a time of t seconds, distance of the northbound person = 4t ft distance of the other person = 5t ft They walk at an angle of 45° to each other. By the cosine law: x^2 = (4t)^2 + (5t)^2 - 2(4t)(5t)cos45 = 41t^2 - 40t^2 (√2/2...
March 3, 2016

Algebra
so you have an arithmetic series with a = 30,000 , d = 2300 sum(10) = (10/2)(60000 + 9(2300) ) = 403,500
March 3, 2016

mathematics
The way you typed it, all is good, the expression would be real and defined for all values of x but... if you meant: 5x+4÷√(8-4x) , then we have two concerns 1. to be real, 8-4x ≥ 0 -4x ≥ -8 x ≤ 2 2. to be defined: 8-4x ≠ 0 -4 ≠ -8 x...
March 3, 2016

Math
speed on first part ---- x km/h speed on return trip -- x+2 km/h time on first trip = 42/x time on 2nd trip = 42/(x+2) 42/x - 42/(x+2) =1/2 multiply each term by 2x(x+2) 84(x+2) - 84x = x(x+2) 84x + 168 - 84x = x^2 + 2x x^2 + 2x - 168 = 0 (x-12)(x+14)=0 x = 12 or x =-14, let&#...
March 3, 2016

Mathematics
Please don't post the same problem again under a different name. Once will do. I just did this for you
March 3, 2016

Maths
In my diagram, I have the perpendicular from T go PC meeting PC at S, giving me 2 right angled triangles. In triangle CST: tan30° = 6/CS CS = 6/tan30 in triangle PST: tan40° = 6/SP SP = 6/tan40 PC = CS+SP = .... you do the button-pushing
March 3, 2016

Finance
I am not familiar with US mortgage laws. What is this "3.5% closing cost" ? so is the original mortgage: add 3.5% to 225,000, then take 90% of that? That would be 225,000(1.035)(.9) = $209,587.50 confirm that before I proceed
March 3, 2016

Math
(-1,14), (0,10), (1,8), (2,?), (3,10), (4,?) and (5,20) the missing values should be like: (-1,14), (0,10), (1,8), (2,8), (3,10), (4,14?) and (5,20) Now if you put those same x value into the straight line you get: (-1,6), (0,7), (1,8), (2,9), (3,10), (4,11), and (5,12) Notice...
March 3, 2016

math
Join A and B to O, the centre of the circle So we have triangle ABO with all 3 sides known. We can use the cosine law to find angle Ø 6^2 = 9^2+9^2-2(9)(9)cosO 162cosØ = 126 cosØ = 126/162 = 7/9 Ø = 38.94...° (I stored it in calculator's ...
March 3, 2016

Algebra
amount = 6300(1.06)^3 = 7503.40 how did you get your answer ??
March 2, 2016

trigonometry (Course and Bearing)
According to my sketch: tan46°10' = 7/AP AP = 7/ tan46°10' = .... sin46°10' = 7/BP BP = 7/sin46°10' = ....
March 2, 2016

Trig
Of course I can't see where your Ø is let's assume it is opposite the smallest side. 10^2 = 17^2 + 20^2 - 2(17)(20)cosØ 680cosØ = 589 cosØ = 589/680 Ø = appr 29.98° If otherwise, make the necessary changes
March 2, 2016

Math
1/2 ÷ 1/8 =
March 2, 2016

Math
be more specific please
March 2, 2016

Algebra
ummh, notice that two of the terms has a single decimal place with that decimal being an even number What happens when you multiply any even number by 5 ?
March 2, 2016

finance
PV = 3000(.96) + 3000(.96)^2 or PV = 3000(1/04)^-1 + 3000(1.04)^-2 depending on how "annual discount rate" is defined in your course. btw, they yield different results.
March 2, 2016

Algebra
pop(chessville) = 50,000(1.07)^n pop(checkerville) = 70,000(.96)^n we want to know when 50,000(1.07)^n ≥ 70,000(.96)^n divide by 10,000 5(1.07)^n = 7(.96)^n take logs of both sides and use rules of logs log5 + nlog1.07 = log7 + nlog.96 nlog1.07 - nlog.96 = log7 - log5 n(...
March 2, 2016

precalculus
Make a reasonable sketch. Using vectors and using R to be the resultant vector: R = (180cos300,180sin300) + (50cos245,50sin245) = (90,-90√3) + (-21.1309.. , -45.31538..) = (68.869.., -201.1996...) Magnitude = √(68.869^2 + (-201.1996..)^2) = appr 212.66 km direction...
March 2, 2016

MATH.
done yesterday http://www.jiskha.com/display.cgi?id=1456884647
March 2, 2016

math
6x^3 + 3x^2 - 9x what about it ?
March 1, 2016

Math
so number = a e^(kt) 10,000 = a e^(3k) 40,000 = a e^(5k) divide the 2nd by the 1st: 4 = e^(2k) 2k = ln4 k = (ln4)/2 so N = a e^( (ln4)/2 t) so we need a a e^(3ln4/2) = 10,000 a = 10,000/8 = 1250 initial count is 1250 bacteria
March 1, 2016

math
what is 6000(1.02)^28 ?
March 1, 2016

Math
time the dog wants to go outside in that time frame = (7/12)(60) = 35 minutes so not wanting to outside = 25 minutes percentage of time not going out = 25/60 = appr 42%
March 1, 2016

Math
prob = 6/10 = 3/5 a cube has 6 sides, so division by 6 would be the model for probs, we need a division by 5 or 10 or 15 ,etc
March 1, 2016

Pre-Calc
did you test the answer in the first equation? It clearly works in the last two equations.
March 1, 2016

Algebra
speed of second train ---- x mph speed of first train --- 2x-10 mph When they meet they would have traveled the same time let that time be t hrs distance gone by first train = tx distance gone by 2nd train = t(2x-1) tx + t(2x-1) = 220 tx + 2tx - t = 220 t(3x-1)=220 t = 220/(3x...
March 1, 2016

Calculus
I have seen this question, where we have to find the other sides so that the perimeter is a minimum, but ... The way it is worded... there is an infinite number of possible lengths. e.g if the side along the x-axis is 5, then the equation of the line passing through (1,1) has ...
March 1, 2016

math
f∘g(x)= f(g(x)) = f(4-x^2) = 4(4-x^2) - 3 simplify do the 2nd one in the same way
March 1, 2016

Math
Did you mean f(x) = √(x+1) ?? I will assume that. f∘g = f(g(x)) = f(3x-5) = √((3x-5) - 5) = √(3x - 10) domain: 3x-10≥0 3x≥10 x ≥ 10/3 ( I will let you switch this to "interval notation, I like the "old way" better) g&#...
March 1, 2016

algebra
first condition: XX2 XX3 XX5 XX7 Second condition: hundreds is twice tens 842 632 422 212 843 .... ... 847................217 There will be 16 of those I will leave it up to you to decide how many of those are prime numbers. (remember, just because a number ends in an odd ...
March 1, 2016

math
Just a simple case of tan38 = h/6.6 h = 6.6tan38° = ....
March 1, 2016

math
amount of 30% solution --- x gal amount of 14% stuff ------ 60-x solve for x .30x + .14(60-x) = .20(60) or if you want two variables: x+y = 60 .30x + .14y = .20(60)
March 1, 2016

math plz help i cant understand this. :'(
Did you plot the points? Look like a trapezoid. AB is a horizontal line, so that AB = 6 AC and BC are parallel So area = (1/2(AC + BC)(AB) = (1/2)(4+6)(6) = 30 square units
March 1, 2016

math :D
Easiest to check would be the median We have an even number of data values, so the median is the average of the two middle numbers. so (23+25)/2 = 24, that rules out #1 and #2 the mode is clearly 25 so we have to find the mean: add them up and divide by 8 to see what you get
March 1, 2016

@ Mary - Calculus
Mary, what part of yesterdays solution did you not like ? http://www.jiskha.com/display.cgi?id=1456770767 Always check to see if your question has been answered before reposting the same thing. That way we avoid unnecessary duplication of work.
March 1, 2016

mathematics
so 75% would be 45 .75x = 45 x = 45/.75 = ...
March 1, 2016

math
distance = 4.9t^2, when t=1 distance = 4.9 m
March 1, 2016

math
This webpage is perfectly suited for your type of problem http://davidmlane.com/hyperstat/z_table.html Just enter the data
February 29, 2016

Calculus
I would assume you are using the cosine law. let the distance between the two tips be x x^2 = 4 + 9 -2(2)(3)cosØ x^2 = 13 - 12cosØ 2x dx/dt = 12sinØ dØ/dt given: dØ/dt = .5 , Ø = π/4 for Ø = π/4 x^2 = 13 - 12cosπ/...
February 29, 2016

Math
equation of tangent: y - 5/3 = (-5/9)(x - 5) y = (-5/9)x + 25/9 + 5/3 y = (-5/9)x + 40/9 check my arithmetic
February 29, 2016

math
Did you make a sketch? On mine I let the top of the tree be A and its bottom be B look at triangle APB. angle ABP = 120° , AP = 4√3, BP = 4 by the sine law: sinA/4 = sin120/4√3 sinA = 4(√3/2)/(4√3) = .5 A = 30° so angle APB = 180-120-30 = 30°
February 29, 2016

math
Make a little diagram of what actually happens. After the first bounce, the ball goes up and down 2/3 of it previous bounce, but the first event can be considered only half a bounce. so I am going to consider this to be a geometric series, pretending the first bounce is ...
February 29, 2016

math
I see 2 similar triangles. let length of Christa's shadow be x ft let length of Glad's shadow be y ft so 5/x = 6/y 6x = 5y we also know x+y = 15 or y = 15-x sub into the first: 6x = 5(15-x) 6x = 75-5x 11x = 75 x = 75/11 ft = appr 6.82 ft y = 15-75/11 = 90/11 ft = appr ...
February 29, 2016

math
just use the formula PV = 1000(1.05)^-8 = ...
February 29, 2016

math
I will assume this is "simple interest" let the rate be r, let the principal be p so (15/12)(rp) = 455 rp = 364 for only 10 months interest = (10/12)(rp) refund = 455 - (10/12)(rp) = 455 - (5/6)(364) = $151.67
February 28, 2016

geometry
Ladder is 12 feet out and 16 ft up, A VERY UNSAFE WAY TO PUT THE LADDER!! length of ladder --- L L^2 = 12^2+16^2 = 400 L= √400 = 20 new position: base = 14 , height = ? , L = 20 solve: h^2 + 14^2 = 20^2
February 28, 2016

math
Good grief, haven't seen that type of question in about 50 years. didn't know they still used it . I will describe the method and then attempt to explain what happened. They are using the word "normal" to mean perpendicular. e.g. in your equation, 2x+3y - 5...
February 28, 2016

math
sinx < -√3/2 consider sinx = -√3/2 by the CAST rule and knowing that sin 30° = +√3/2 x = 210° or x = 330° also, you should know the general shape of the sine curve. from the above the curve would be below -√3/2 between 210° and 330&...
February 28, 2016

Geometry
recall that sin^2 Ø + cos^2 Ø = 1 so sin^2 Ø + 9/64= 1 sin^2Ø = 55/64 sinØ = √55/8 then cscØ = 8/√55 or 8√55/55
February 28, 2016

Pre-Calculus
Important info at the end: "with equal amounts invested in short- and intermediate-term bonds. " So let each of those amounts be x then the amount invested at long-term be 100,000 - 2x He wants to end up with a 5.1% profit on the total 100,000 or $5100 Now it is easy...
February 28, 2016

Algebra
I will assume you made a diagram. On my diagram, I have each of the long sides as y, and each of the 3 shorter sides as x so we have 3x + 2y = 440 y = (440 - 3x)/2 = 220 - (3/2)x area = xy = x(220 - (3/2)x) = 220x - (3/2)x^2 from the subject title, I assume you don't take ...
February 28, 2016

math
those solutions where 0 ≤ x ≤ 2π 2cos^2x-5cosx+2=0 this is a standard quadratic where your variable is cosx How about doing this ? let t = cosx then we have 2t^2 - 5t + 2 = 0 , which factors to (2t - 1)(t - 2) = 0 t = 1/2 or t = 2 so cosx = 1/2 or cosx = 2 ...
February 28, 2016

maths
I can't see any other way than listing the possible cases and finding the total score for each case. Using the first letter of each outcome, we could have BBBB -- 36 BBBS -- 34 BBBT -- 31 BBBO -- 28 BBSS -- 32 BBTT -- 26 BBOO -- 20 BBST -- 29 BBSO -- BBTO etc, watch for ...
February 28, 2016

math
hard to get the spacing correct, I will use ** for spacing 3|2**0**-1**0***7****1 ******6**18**51*153*480 ***2**6**17**51*160*481 f(3) = 481
February 28, 2016

Math
prob(hit) = .42 prob(no hit ) = 1 - .42 = .58 at least 2 hits out of 4 ---> exclude : no hits, 1 hit prob(no hits) = C(4,0)(.42)^0 (.58)^4 = .113165 prob(1hit) = C(4,1)(.42)(.58)^3 = .32779 prob(at least 2 hits) = 1 - (.113165 + .32779) = appr .559 or you could do prob(...
February 28, 2016

math
Tell me what you got, then we'll both be happy
February 28, 2016

math
This is almost the same kind of question that I answered for you here : http://www.jiskha.com/display.cgi?id=1456693077 Did you look at it, and learn from it? I will give you one hint for this one: cos (2Ø) = cos^2 Ø - sin^2 Ø let me know how you made out.
February 28, 2016

math
remember cos^2 Ø + sin^2 Ø = 1 .36 + sin^2 Ø = 1 sin^2 Ø = .64 sinØ = .8 sin 2Ø = 2sinØcosØ = 2(.8)(.6) = .96 2Ø = sin^-1 (.96) or arcsin(.96)
February 28, 2016

Geometry/Algebra
welcome!
February 28, 2016

Geometry/Algebra
Make a sketch of a right-angled triangle ABC with angleB = 90° Draw in the altitude from C to hypotenuse AC to meet it at D. You now have 3 similar right-angled triangles. (easy to see by considering the angles) I will list them, with corresponding vertices in the same ...
February 28, 2016

Math
Why could you not check them?? is (1/8)% of 32 = .04 ?? (1/800)(32 = 32/800 = .04 , so YES x(1.8) = 3 x = 3/1.8 = 1.6666.. or 166.66..% or 166 2/3% check that: take 166.66..% of 1.8 = (166.666../100 )(1.8) = 3
February 28, 2016

math
a+d = 50 a + 4d=65 subtract them 3d = 15 d = 5 then a+5=50 a=45 term40 = a + 39d = 45 + 39(5) = 240
February 28, 2016

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