Friday

May 27, 2016
Total # Posts: 40,859

**Algebra**

I assume you want to know how many miles in city and highway. Well, take a look at the data: miles = gals * mi/gal so total miles: 15.867*15 = 238 If there were c city miles, then the rest (238-x) were highway miles. So, x/13 + (238-x)/30 = 15.867 x = 182 so, 182 city miles 56...
*May 24, 2016*

**Algebra**

since distance = speed * time, 3(x+3) = 7(x-3)
*May 24, 2016*

**math**

(80000-50000)/50000 = 3/5 = 60%
*May 24, 2016*

**algebra**

however, assuming you meant y = -1/3 x + 1/2, if you rearrange things you have 6x + 18y = 9 1/3 x + y = 1/2 or 6x+18y = 9 2x+6y = 3 you can see that they are the same line.
*May 23, 2016*

**Math**

don't you have the formula? Just plug in your numbers and we can check your answer.
*May 23, 2016*

**Math**

correct.
*May 23, 2016*

**Math**

rearrange things to a single format: x+6y=4 2x+12y=8 Now you can see that they are really the same line.
*May 23, 2016*

**Math**

well, you must have tan2x = 0 or sinx = 1 so, you are almost right. tan2x=0 if 2x = 0 or π or 2π or 3π so, x = 0, π/2, π, 3π/2 sinx = 1 if x = π/2, so that does not add any solutions to the list.
*May 23, 2016*

**Math**

If all the numbers are expressed as multiples of 10^-7, they are a: 620 b: 12.3 c: 52000000000 d: 370 should be a bit easier now, eh?
*May 23, 2016*

**College Algebra math**

35 + √(37^2 - 35^2)
*May 23, 2016*

**pre algebra Is it A,B,C or D?**

where did you come up with 3/11? tossing the coin and picking a letter are independent events, so the theoretical probability is just 1/2 * 1/5 = 1/10
*May 23, 2016*

**Geometry**

well, s = rθ
*May 23, 2016*

**Pre algebra Am I right??**

looks good to me
*May 23, 2016*

**math**

A farmer has dogs and chickens running around in his backyard. There are a total of 36 animals, and the farmer counts a total of 56 legs. The farmer can use a system of equations to determine how many of each animal there are. He claims that one of the equations in the system ...
*May 23, 2016*

**Math**

C: 3 is prime and odd
*May 23, 2016*

**ALGEBRA**

nope. You have to account for both events. P(odd) = 3/4 P(even) = 1/4 so, P(odd,even) = 3/4 * 1/4
*May 23, 2016*

**Algebra**

11 bills in all The two bills must be 5,20 or 20,5 p = (2/11 * 4/10) + (4/11 * 2/10) = 8/55
*May 23, 2016*

**Algebra**

correct
*May 23, 2016*

**Math**

for the product to be even, you must have either m even or m+p even A works, because odd+odd is even B fails -- odd*odd = odd C works whether p is even or odd, so it's not true that p must be even. D the same
*May 23, 2016*

**Math**

so did I
*May 23, 2016*

**Math**

yes it would
*May 23, 2016*

**Math**

right on.
*May 23, 2016*

**Math (Vectors)**

if the angle A is drawn in the standard position, tan(A) = y/x
*May 23, 2016*

**MATHS TRIGONOMETRY**

you have sinθ = 2/3 if sin and cos are both positive, then θ is in QI. So, now draw the triangle. y = 2 r = 3, so x = √5 Now just use those values and the fact that sinθ = y/r cosθ = x/r tanθ = y/x to answer the questions. The last one should be ...
*May 23, 2016*

**math**

rearranging things a bit, you have 3y^2 - y - 6 = 0 y = (1±√(1+72))/6
*May 23, 2016*

**math hurry**

1 nope. subtract exponents when dividing 2 nope. same reason 3 nope. 4^-2 = 1/4^2 = 1/16 4 nope. using the logic of the first 3 problems, 5^0 = 5^1/5^1 = 5/5 = 1 any number to the zero power is 1. #6 I suspect a typo, as they are all wrong #7 B (But I suspect that you did it ...
*May 23, 2016*

**Math Can you help me?**

gains are positive, losses are negative, so he ends up at 0+7-4+12 = 15
*May 23, 2016*

**math**

certain superstores will often price match or even beat a competitor's price by 10%.the function g(x)=0.90x represents the sale price of a piece of merchandise at such a superstore.the function f(x)=0.13x represents the HST owed on a purchase with a selling price of x ...
*May 23, 2016*

**Math**

think of it kind of like a Venn diagram. P(divisible by 2 or 5) = P(by 2)+P(by 5) - P(by 10) So just count the number of integers divisible by 2 or 5, and you have counted the multiples of 10 twice. Divide that answer by 1000 to get the probability.
*May 23, 2016*

**Math; Solve by Graphing**

clearly D is out, since it has nothing to do with the solution. Similarly, B and C are out, because it does not matter where the lines hit the axes. The solution is where both equations are true. Since each represents a line, that is where the lines intersect. So, (A) is the ...
*May 23, 2016*

**Math**

first, review what complementary and supplementary mean. An angle and its complement sum to 90 degrees. So, what number do you add to 52 to get 90? similarly for supplement.
*May 23, 2016*

**analytic geometry**

The two lines you named are parallel. They cannot be the asymptotes of an hyperbola.
*May 23, 2016*

**math**

c = kq
*May 23, 2016*

**Geometry,Math**

you are correct that a cylinder has less surface area than a rectangular prism.
*May 22, 2016*

**Math**

A farmer has dogs and chickens running around in his backyard. There are a total of 36 animals, and the farmer counts a total of 56 legs. The farmer can use a system of equations to determine how many of each animal there are. He claims that one of the equations in the system ...
*May 22, 2016*

**Math**

total marbles = 22 so, P(blue,yellow) = 9/22 * 13/21
*May 22, 2016*

**science**

well, rice grains are bigger than sugar grains. So just use a fine sieve. Sugar goes through, rice stays behind.
*May 22, 2016*

**Math**

A farmer has dogs and chickens running around in his backyard. There are a total of 36 animals, and the farmer counts a total of 56 legs. The farmer can use a system of equations to determine how many of each animal there are. He claims that one of the equations in the system ...
*May 22, 2016*

**grade 9**

28*22*h = π*3.5^2*40 h ≈ 2.5m
*May 22, 2016*

**Math**

A farmer has dogs and chickens running around in his backyard. There are a total of 36 animals, and the farmer counts a total of 56 legs. The farmer can use a system of equations to determine how many of each animal there are. He claims that one of the equations in the system ...
*May 22, 2016*

**Easy Math**

I think you are correct. If the points in order are A,B,C then each point can be the start of a ray, and each ray can go in two directions. But rays from A and C must also include B. So, the rays are AB (or AC, which is the same) BA and BC CB (or CA)
*May 22, 2016*

**pre-algebra**

there are infinitely many possible values: 2(30+L) >= 768 30+L >= 384 L >= 354 so, any number at least 354 will work. I suspect you did not ask the right question.
*May 22, 2016*

**Algebra**

2(w + 3w-4) = 48 find w, and then you can get the length.
*May 22, 2016*

**integral calculus**

Draw a cross-section. If the oil is at depth y, then the width of the thin rectangle of oil is 2x, where (3-y)^2 + x^2 = 9 x = √(6y-y^2) So, the weight of oil for that thin sheet is 2x*8*60 dy and the total work to lift all the oil out of the top of the tank is thus &#...
*May 22, 2016*

**maths**

Fix the typo (ax^2+bx+x ?), and is the curve tangent to the line?
*May 22, 2016*

**math**

assuming the strides take the same amount of time, the dog wins. 1.30 * 0.70 = 0.91
*May 22, 2016*

**Mathematics**

well, S10 = 10/2 (1+19)
*May 22, 2016*

**math (check answer)**

why would the math class have students whose birthdays are skewed?
*May 21, 2016*

**math**

since the events are independent, just multiply their probabilities. For the first, that would be 1/6 * 1/2 and the others likewise
*May 21, 2016*

**Math**

just crank out the algebra. The result is 4 note that w = cis(2pi/3) or cis(4pi/3)
*May 21, 2016*

**expansion help**

scroll down and down at http://www.wolframalpha.com/input/?i=%281%2B%281%2Fx^3%29%29
*May 21, 2016*

**Math**

f+s = 72 f+2 = 3(s+2)-4 now just crank it out.
*May 21, 2016*

**Math**

4 hours = 240 minutes. So, the fraction of the tank filled in one minute is 1/15 - 1/240 = 15/240 = 1/16 So, it will take 16 minutes to fill the leaking tank
*May 21, 2016*

**geometry**

an unusual position -- the ladder is not on the ground. I expect you mean the foot of the ladder is one meter from the wall. I assume you want the height of the top of the ladder. If the height up the wall is h, then 1^2 + h^2 = 20^2
*May 21, 2016*

**Middlesex**

recall that if a is a root, then (x-a) is a factor of f(x). So, you have (x-3)(x+6) = 0
*May 21, 2016*

**ordinary differential equation**

well, it's clear that (m-3)^3 = m^3 - 9m^2 + 27m - 27 now just proceed as usual to solve this type of equation.
*May 21, 2016*

**math**

depends on the distance, no? But, you know that after n seconds, the distance traveled will be Sn = n/2 (2*1.5+0.4(n-1)) cm
*May 21, 2016*

**math**

z = 1250ln(yx^2)+45(y^2+x)(x^3 -2y)-(xy)^1/2 see ∂z/∂x at http://www.wolframalpha.com/input/?i=1250ln%28yx^2%29%2B45%28y^2%2Bx%29%28x^3+-2y%29-%28xy%29^1%2F2 But you will need some values for x and y if you want a numeric value.
*May 21, 2016*

**Maths**

surely you can plot each of these curves. But just to remind you, http://www.wolframalpha.com/input/?i=plot+y%3Dsinx,+y%3Dcosx,+y%3Dcosx-sinx
*May 21, 2016*

**logarithm math-need help!!!!**

If we let u = log_4(x) then x = 4^u and we have 5u + 48/u = 4^u/8 the solution to this is u=4 so, x=4^u = 256
*May 21, 2016*

**math**

a factor of 1000 means that one 6 is 3 places to the left of the other. That is, the number must contain the digit string 6336 That means that the other 3 must go on the left or right end.
*May 21, 2016*

**Mathematics**

w(w+3) = (w/2)(w+3 + 5) w = 2 be sure to check that this works.
*May 21, 2016*

**geometry**

dv/dt = 4πr^2 dr/dt da/dt = 8πr dr/dt (dv/dt)/(da/dt) = r/2 so, when r=10, da/dt = 240 cm^2/s
*May 21, 2016*

**Math**

a mess, is what. Still, I will try to parse your garbled sentence. 9 - 3 ÷ 1/3 + 1 = 1 If that's not what you meant, try using some parentheses to get what you want.
*May 21, 2016*

**maths**

original: (d-3)/d now, adding 1's, we have (d-3+1)/(d+1) = 5 Hmmm. I suspect a typo, since d is not an integer.
*May 21, 2016*

**math**

$(40*0.90-10)*1.45 = $37.70
*May 20, 2016*

**math**

clearly the numbers in question must have 6336 so, there are two 3's left over, which must go on the ends: 36336 63363
*May 20, 2016*

**Algebra**

you show B and D the same. Pick the one which is really 6^x x^6 is not what you want. That is (0,0),(1,1),(2,64)...
*May 20, 2016*

**math**

oh come on. either 4cotx+3 = 0 cotx = -3/4 or cotx-1 = 0 cotx = 1 In the first case, x will be in QII or QIV on the second case, x will be in QI or QIII
*May 20, 2016*

**math**

since csc^2 = 1+cot^2, 4(1+cot^2x)-7 = cotx 4+4cot^2x-7 = cotx 4cot^2x - cotx - 3 = 0 (4cotx+3)(cotx-1) = 0 Now it's easy, right?
*May 20, 2016*

**Algebra**

1*57 + 6*x = 5(57+x)
*May 20, 2016*

**pre-algebra**

x + 1/3 x = 84 4/3 x = 84 ...
*May 20, 2016*

**HELP ME ! DESPRATE MATH STUDENT !!**

you cannot compare those integers with 6 1/3 ? You are in deep doodoo. At the very least, grab a calculator and subtract each from 6.333333 If the result is positive they are less; if negative, they are greater.
*May 20, 2016*

**HELP ME ! DESPRATE MATH STUDENT !!**

well, geez, did you try a few values? 3*0 - 4 <= 15 ? 3*6 - 4 <= 15 ? and so on. or, algebraically, 3x-4 <= 15 3x <= 19 x <= 19/3 so, how many of those values fit the bill?
*May 20, 2016*

**math**

original value: n/d new value: 1.60n/0.80d = 2n/d so, it has grown by 100%
*May 20, 2016*

**math**

5/300 x = 475/100
*May 20, 2016*

**math**

6/5 as many people, so 5/6 as much time
*May 20, 2016*

**math**

195/15 * 8
*May 20, 2016*

**math**

v/i = 5/2, so v = 5i/2 v = i+42 5i/2 = i+42 so, i=28 and v=70 You want to find x such that (70-x)/(28+x) = 3/4 I expect you can handle that part.
*May 20, 2016*

**math**

420/5 = 84 so, multiply all the values by 84 and you have 504:420:252 Now just add all that up.
*May 20, 2016*

**math**

15 + x = -84 ...
*May 20, 2016*

**MATH HELP PLEASE !!**

clearly, it also increases by 5 (x+5)-3 = (x-3)+5
*May 20, 2016*

**Math (Vectors)**

the angle θ between the vectors is 55-25 = 30°. u•v = |u|*|v|*cosθ now just plug in your numbers.
*May 20, 2016*

**Math/ Ratios**

ratios are just fractions. So, you have a = h (a-23)/(h-7) = 3/4 now just solve for a,h and then a+h
*May 20, 2016*

**Pre Algebra**

5C 6D 9 correct 16C 19B 20A 21C Review your methods and try them till you get these answers.
*May 20, 2016*

**MATH FACTORING**

does not factor with real numbers. The discriminant is negative.
*May 20, 2016*

**Math Help!!**

well, is there any chance of rolling a zero?
*May 20, 2016*

**pre cal**

y = 4√(2x/3) - 1 y+1 = 4√(2x/3) just square both sides and you have y^2+2y+1 = 16(2x/3) That is clearly a parabola opening to the right.
*May 20, 2016*

**calculus**

why all those useless words? Use some math symbols! dy/dx = 3y/x dy/y = 3/x dx lny = 3lnx + c or, lny = ln(x^3) + ln(c) (different c) y = cx^3 y(1)=1 means c=1 y = x^3 I expect that you can determine the domain for that...
*May 20, 2016*

**math**

looks right to me.
*May 20, 2016*

**Algebra**

while 40 = 40*1, 20 ≠ 40*2 so, your first guess is wrong. However, note that x*y=40 for all the items.
*May 20, 2016*

**trigonometry**

I'll just use x for the angle sin^2(x)/(1-cos(x) = (1-cos^2(x))/(1-cos(x)) = (1+cosx)(1-cosx)/(1-cosx) = 1+cosx
*May 20, 2016*

**math**

of course you do. The perimeter was in inches -- so are the sides. Of course, you could use cm or miles or chains or light-years, but then the numbers would no longer be integers.
*May 20, 2016*

**Calculus (Integration proving)**

can you clarify what (integral, r to none) means? and if you only have dA, why the three dimensions for R?
*May 20, 2016*

**math**

hmmm. good point.
*May 20, 2016*

**math**

do you know the dimensions of a football field?
*May 20, 2016*

**math**

4(x+1)(x+2) = 24 (x+1)(x+2) = 6 I think you know two consecutive integers whose product is 6.
*May 20, 2016*

**Math**

#1 ok #2 ok so, #3 must be ok too, since it is the same as #2!
*May 20, 2016*

**math**

(x + 1/x)^2 = x^2 + 2 + 1/x^2 = 49 so, x + 1/x = 7 or -7
*May 20, 2016*

**calculus**

even without calculus, this one is easy. The x-intercept of y=2x+a is x = -a/2 So, you have a triangle with base 3a/2 and height 3a, so the area is 9a^2/4. If 9a^2/4 = 18, a = √8 check: ∫[-a/2,a] 2x+a dx = 9a^2/4
*May 20, 2016*