Wednesday

May 25, 2016
Total # Posts: 11,830

**Math help**

a. C = 4.70d. b. C = 4.70d - 1 = 4.70*4 - 1 = $17.80. C = 4.70*7 = $32.90.
*April 13, 2016*

**Math help!**

d = 66t.
*April 13, 2016*

**maths**

Vo = 40.000m/3600s = 11.11 m/s. V = Vo + a*t = 0, 11.11 - 0.5t = 0, -0.5t = -11.11, t = 22.22 s.
*April 13, 2016*

**Find the area of the segment of a circle of radious 21 cm and corresponding central angle 30**

As = 30/360 * Ac = 30/360 * 3.14*21^2 = 115.4 cm^2.
*April 13, 2016*

**math**

-16x^2 + 24x + 16 = 0. A. Divide by 8: -2x^2 + 3x + 2 = 0, A*C = -2*2 = -4 = -1 * 4. Sum = -1 + 4 = 3 = B, -2x^2 + (-x+4x) + 2 = 0, (-2x^2-x) + (4x+2) = 0, -x(2x+1) + 2(2x+1) = 0, (2x+1)(-x+2) = 0, 2x+1 = 0, X = -1/2. -x+2 = 0, X = 2. X-intercepts: (-1/2,0), (2,0). B. Since ...
*April 12, 2016*

**Math**

V = 390mi/h[28o]N of W. D = 390mi/h[28o] * 3h = 1170 mi[28o]N. of W. Dn = 1170*Cos28 = Dw = 1170*sin28 =
*April 11, 2016*

**pre algebra**

Width = W cm. Length = W+6 cm. ((W+6)-3)(W+3) = 64 cm^2. (W+3)(W+3) = 64, W^2+6W+9 = 64, W^2+6W-55 = 0, -55 = -5*11, -5+11 = 6 = B, (W-5)(W+11) = 0, W-5 = 0, W = 5. W+11 = 0, W = -11. Original Dimensions: W = 5 cm, L = 5+6 = 11 cm.
*April 11, 2016*

**PHY 1004**

Range = Vo^2*sin(2A/g. A = 30o, g = 9.8 m/s^2.
*April 9, 2016*

**Physics**

1. Basically, a loudspeaker converts electrical energy to sound.
*April 9, 2016*

**Math**

P = Po(1+r)n = 100,000. r = 0.072/2 = 0.036 = Semi-annual % rate expressed as a decimal. n = 2Comp./yr. * t yrs. = 2t Compounding periods. 73,000(1.036)^2t = 100,000. (1.036)^2t = 100,000/73,000 = 1.370, 2t*Log1.036 = Log1.370, 2t = Log1.370/Log1.036 = 8.90, t = 4.45 Years.
*April 9, 2016*

**math**

See previous post.
*April 9, 2016*

**math**

2x^2 + 6x - 5 = 0. Use Quadratic Formula: X = (-6 +- Sqrt(36+40))/4 = (-6 +-(8.72)/4 = 0.679, and -3.68.
*April 9, 2016*

**physics**

P = E^2/R = 120^2/29 = 497 Watts = 0.497 kW. Cost = 0.497 * 5.6 * 7.35cents/kWh.
*April 8, 2016*

**physics**

1. P = E*I = 120 * 15 = 1800 W. 1800/1500 = 1.2 or 1 Dryer. 2. 1500W. = 1.5kW. Cost = 1.5 * 6.3 * 0.078 =
*April 8, 2016*

**Physics**

T = 2pi*Sqrt(L/g) = 6.28*Sqrt(1/1.63) = 4.92 s.
*April 8, 2016*

**physics**

M*g = 20 N., g = 20/M = 20/6.5 = 3.08 m/s^2.
*April 7, 2016*

**Physics**

Vo = 217km[26.9o], a. Xo = 217*Cos26.9 = b. Yo = 217*sin26.9 =
*April 7, 2016*

**Algebra**

Sqrt(363) - 3Sqrt(27) = Sqrt(121*3) - 3Sqrt(3*9) = 11Sqrt(3) - 3*3Sqrt(3) = 11Sqrt(3) - 9Sqrt(3) = 2Sqrt(3).
*April 7, 2016*

**math**

4c =< 9, C =< #2.25 Per doz.
*April 7, 2016*

**Math**

Grandfather: X years old. Father: x-26 years old. Son: (x-26)-29 = x-55. x + x-26 + x-55 = 135, 3x - 81 = 135, 3x = 216, X = 72, x-26 = 46, x-55 = 17.
*April 7, 2016*

**Sarah**

Can you explain your problem in words instead of drawing a diagram? I understand electrical circuits, but I don't understand your diagram.
*April 7, 2016*

**Math**

Beginning bal. = 1761.
*April 5, 2016*

**algebra**

V1 = X km/h, V2 = x + 18 km/h. d1 + d2 = 150 km. 3x + 3(x+18) = 150, 6x + 54 = 150, 6x = 96, X = 16 km/h, x+18 = 16 + 18 = 34 km/h = V2 = Speed of the faster car.
*April 5, 2016*

**science**

Vo = 180m/s[55o]. a. Range = Vo^2*sin(2A)/g = 180^2*sin(110)/9.8 = 3107 m. b. Same procedure as "a" except g = 1.6 m/s^2.
*April 5, 2016*

**physics**

Xc = 1/WC = -1/(314.2*20*10^-6) = -159.2 Ohms. Z(Ohms) = 30 -j159.2 = 162[-79.3o]. I = E/Z = 100[0o]/162[-79.3] = 0.617A[79.3o].
*April 4, 2016*

**physics**

a. Xl = E/I = 3.6/2.5*10^-4 = 1.44*10^4 Ohms. b. Xl = 2pi*F*L = 14,400, L = 14,400/(6.28*1.6*10^6) = Henrys.
*April 4, 2016*

**Science**

V1 = 15 + 3 = 18 km/h. V2 = 15 - 3 = 12 km/h.
*April 4, 2016*

**MATH**

P = Po + Po*r*t = 2200 + 2200*(0.07/360)*100 = P = 2200 + 2200*(0.07/365)*100 =
*April 4, 2016*

**math**

Correction: 4- 1 1/2 = 2 1/2 Pizza without pepperoni. 1 1/2 - 5/6 = 3/2 - 5/6 = 9/6 - 5/6 = 4/6 = 2/3 Pizza with pepperoni remaining. 4 - 5/6 = 24/6 - 5/6 = 19/6 = 3 1/6 Pizza left. (2/3)/(19/6) = 2/3 * 6/19 = 12/57 = 4/19 Of total pizza left has pepperoni.
*April 3, 2016*

**math**

4- 1/1/2 = 2 1/2 Pizzas without pepperoni. 2 1/2 - 5/6 = 5/2 - 5/6 = 15/6 - 5/6 = 10/6 = 5/3 = 1 2/3 pizzas with pepperoni remaining. 4 - 5/6 = 24/6 - 5/6 = 19/6 = 3 1/6 Pizzas left. (5/3)/(19/6) = 5/3 * 6/19 = 30/57 = 10/19 Of total pizza left has pepperoni.
*April 3, 2016*

**math**

g = C/5 + J/5 + S/5. C = Classic CDs, J = Jazz CDs, and S = Soft rock CDs.
*April 3, 2016*

**Physics**

Vo = 2.19m/s[25.1o]. Yo = 2.19*sin25.1 = 0.93 m/s. a. Y^2 = Yo^2 + 2g*h = 0, 0.93^2 - 19.6h = 0, -19.6h = -0.865, h = 0.0441 m. b. Y = Yo + g*t = 0, 0.93 - 9.8t = 0, -9.8t = -0.93, t = 0.095 s. c. V = Vo = 2.19 m/s.
*March 31, 2016*

**Physics**

F = 32N[30o] + 56N[0o]? + 38N[60o] = 27.7+16i + 56 + 19+32.9i = 102.7 + 48.9i = 118N{25.5o]. F = M*a, a = F/M = 118[25.5o]/118 = 1 m/s^2[25.5o].
*March 31, 2016*

**Mechanics**

Wb = M*g = 6 * 9.8 = 58.8 N. = Wt. of block = Normal(Fn). Fap-Fk = M*a, 22.5-Fk = 6*1.25 = 7.5, Fk = 15 N. = Force of kinetic friction. u = Fk/Fn = 15/58.8 = 0.255.
*March 30, 2016*

**Physics- Circuits Current & Voltage Problem**

The above note does not apply to R2.
*March 29, 2016*

**Physics- Circuits Current & Voltage Problem**

E1 = 40V., R1 = 80 Ohms. E2 = -360V., R2 = 20 Ohms. E3 = 80V., R3 = 70 Ohms. Ro = 200 Ohms. Convert the 3 voltage sources to a single current source: Is = E1/R1+E2/R2+E3/R3 = 40/80 - 360/20 + 80/70 = -16.9A., Downward. Determine current through Ro: 1/Rs = 1/R1+1/R2+1/R3 = 1/80...
*March 29, 2016*

**math**

Adult: $X each. Student: $Y each. Eq1: 7x + 16y = 120. Eq2: 13x + 9y = 140. Multiply Eq1 by 13, Eq2 by 7, and subtract: 91x + 208y = 1560 91x + 63y = 980 Diff.:145y = 580. Y = $4.00.
*March 29, 2016*

**Physics**

V = Vo + a*t = 0 + 2*2 = 4 m/s. a. d1 = v*t = 4 * 4 = 16 m. V = Vo + a*t = 0, 4 + a*10 = 0, a = -0.4 m/s^2. V^2 = Vo^2 + 2a*d2 = 0, 4^2 - 0.8*d = 0, -0.8d2 = -16, d2 = 20 m. b. Vavg = (d1+d2)/(t1+t2) = (16+20)/(4+10) = 2.57 m/s.
*March 29, 2016*

**Physics**

Vo = 108,000m/3600s = 30 m/s. V = Vo + a*t = 0, a = -Vo/t = -30/5 = -6.0 m/s^2.
*March 29, 2016*

**PHYSICS**

Add a resistor in series with the coil: R+12 = E/I = 10/0.0025 = 4,000, R = 4,000-12 = 3,988 Ohms.
*March 29, 2016*

**College Algebra**

a. Y = 2^w + 7.
*March 28, 2016*

**math\**

Po*0.03*1 + (Po+750)*0.05*1 = 157.50. 0.03Po + 0.05Po + 37.50 = 157.50, 0.08Po = 120, Po = $1500 @ 3%. 1500 + 750 = $2250 @ 5%.
*March 28, 2016*

**science**

M*g = 40*9.8 = 392 N. Fp = 392*sin20 = 134.1 N. = Force parallel to the incline = Force required to pull the body up the incline.
*March 28, 2016*

**Math**

V = -2000t + 20,000 = 14,000. t = ?.
*March 27, 2016*

**Math**

A. J(2,1), K(-5,1), L(-5,2), M(2,2). B. L = 2 - (-5 = 7, W = 2-1 = 1. P = 2L + 2W = 2*7 + 2*1 = 16 Units.
*March 26, 2016*

**Physics**

a. P = E^2/R = (120)^2/R = 5.00 W., R = (120)^2/5 = 2,880 Ohms. P = (230)^2/2880 = 18.4 W. b. U.S.A.: 120I = 5.0, I = 0.0417A. Rome: 230I = 18.4, I = 0.08A. I = 1.2 * 0.0417 = 0.050A = Current at which the razor will be damaged. Yes. c. Np/Ns = Vp/Vs = 230/120 = 1.92/1. d. R...
*March 26, 2016*

**Physics**

Vt = 72,000m/h * 1h/3600s = 20 m/s. a. Fp = (Vs+Vp)/(Vs-Vt) * Ft =(343+0)/(343-20) * 600 = 637.2 Hz. b. Fp = (Vs-Vp)/(Vs+Vt) * Ft =
*March 26, 2016*

**physics**

M1*V1 + M2*V2 = M1*V3 + M2*V4, 2*10 + 3*0 = 2*V3[30o] + 3*4, 20 = 2V3[30o] + 12, 2V3[30] = 8. 2[30] = 8/V3, 1.732 + i = 8/V3, 8/V3 = 2, 2V3 = 8, V3 = 4 m/s. = Speed of 2kg ball.
*March 25, 2016*

**physics**

t = 54rev * 1min/3500rev = 0.0154 min. = 0.93s. Vo = 3550 rev/min * 6.28rad/rev * 1min/60s = 372 rad/s. V = Vo + a*t = 0, a = -Vo/t = -372/0.93 = -400 rad/s^2.
*March 25, 2016*

**Physics**

Work = F*d = Mg * d = 20*9.8 * 10 = 1960 J.
*March 25, 2016*

**physics**

Incomplete.
*March 25, 2016*

**Physical Science**

Density = 500g/50cm^3 = 10g/cm^3.
*March 24, 2016*

**Science**

Defective light bulb, defective switch, dead battery or miswired.
*March 24, 2016*

**Engineering Accounting**

The Equation used most often for home and auto loans: P = Po*r*T/(1-(1+r)^-T) (Po*0.01*72)/(1-1.01^(-72)) = 38,060, 0.72Po/0.51150 = 38,060, 1.41Po = 38,060, Po = $27,038.67. = Cost of car.
*March 23, 2016*

**Engineering Accounting**

P = 3500 + (480*72) = 38,060. P = Po(1+r)^n = 38,060, r = 0.12/12 = 0.01/mo., n = 72 Compounding periods. Po(1.01)^72 = 38,060, 2.047Po = 38,060, Po = $18,592.16. = Price of car.
*March 23, 2016*

**Engineering Accounting**

Price = 3500 + (480*72) =
*March 23, 2016*

**Business math**

1. P = Po(1+r)^n. r = 0.046/2 = 0.023 = Semi-annual % rate. n = 2Comp./yr. * 8.5yrs. = 17 Compounding periods. P = 26,000(1.023)^17 = $38,270.058. 8.5yrs. = 102 Months. 38,270.058/102 = $375.20/Mo. 2. I = 38,270.06 - 26,000 = $12,270.06.
*March 23, 2016*

**Math**

I = Po*r*t = (1350-300)*(0.1425/12)*1 = $12.47. I = 1350*(0.1425/12)*1 = $16.03. Int. Saved = 16.03 - 12.47 =
*March 23, 2016*

**math**

T = Time until app. 60*(T-10/60) = 45*(T+5/60), 60T-10 = 45T + 3.75, 15T = 13.75, T = 0.91667 h = 55 Min.
*March 23, 2016*

**math !**

Glad I could help!
*March 23, 2016*

**math !**

A = 15 * 6*8 = 720 Sq. in.
*March 23, 2016*

**math**

A = 6*4 + 3*8 == 48 Ft^2, Cost = 20 * 48 =
*March 23, 2016*

**Math**

(14 2/9)% = (128/9)% = (128/9)%/100% = 128/900 = 32/225 = the ratio.
*March 23, 2016*

**math**

12/4 = L/6, L = ?.
*March 22, 2016*

**Physics**

M1*V1 + M2*V2 = M1*V + M2*V, 64.8*9.2 + 24.4*0 = 64.8V + 24.4V, 596.16 = 89.2V, V = 6.68 m/s.
*March 22, 2016*

**Physics**

a. My answer: 207.5 J/s = 207.5 W. b. Work = F*d = Mg*d = 2400*9.8 * 1.3 = 30,576 Joules. T = 30,576J. * 1s./207.5J. = 147.4 s.
*March 22, 2016*

**physics**

Incomplete.
*March 22, 2016*

**Physics**

7.90h * 3600s/h = 28,440 s. = 2.84*10^4 s. P = 5.90*10^6/2.84*10^4 = 207.5 J/s. = 207.5 Watts.
*March 22, 2016*

**Physics**

a. 6.28/360o = x/82.9o, x = 82.9 * 6.28/360 = 1.45 Radians. b. 6.28rad/rev * 6revs =
*March 21, 2016*

**Whats the answer**

2-11x^2-8x+6x^2 = -5x^2-8x+2.
*March 21, 2016*

**electronics**

What does Tr and ZT mean?
*March 20, 2016*

**physics 101**

30mi/h * 1600m/mi * 1h/3600s. =
*March 20, 2016*

**algebra**

Sqrt(39sqrt(6-4)) == Sqrt(39sqrt2) = Sqrt(55.15) = 7.43
*March 20, 2016*

**Algebra**

L = Sqrt(x^2+Y^2) = Sqrt(9^2+13^2) = 15.8 Ft.
*March 20, 2016*

**Math**

TanA = 60/91 = 0.65934, A = 33.4o. E. of N.
*March 20, 2016*

**Math**

X => 3, Y = 2.
*March 19, 2016*

**math help**

See your previous post.
*March 18, 2016*

**Math (Grade 12)**

1. Equity = 367,685-108,653. 2. 0.564 * Equity =
*March 18, 2016*

**Physics**

V^2 = Vo^2 + 2a*d, a = (V^2-Vo^2)/2d = (50^2-300^2)/0.08 = -1,093,750 m/s^2. F = M*a = 0.025 * (-1,093,750) =
*March 18, 2016*

**science**

d. 6.67 g/mL.
*March 17, 2016*

**Phy**

See previous post: 3-17-16, 10:58 AM.
*March 17, 2016*

**Phy**

T1 = T2, T1*Cos45 - T2*Cos45 = 0. So, the hor. components cancel. T1*sin45 + T2*sin45 = 20, Replace T2 with T1: T1*sin45 + T1*sin45 = 20, 2T1*sin45 = 20, 1.414T1 = 20, T1 = 14.14 N. = T2.
*March 17, 2016*

**math**

Po = $3,500, T = 3 Years, P = 36 * 104.50 = $3762. Int. = P-Po = 3762 - 3500 = $262. Int. = 3500*r*3 = 262, 10,500r = 262, r = 0.025 = 2.5% = APR.
*March 16, 2016*

**physics**

Correction: Vs = 343 m/s. (343+14)/(343-75) * 1000 = 357/268 * 1000 = 1332 Hz.
*March 16, 2016*

**physics**

Fr = (Vs+Vt)/(Vs-Vc)*Fc = (443+14)/(443-75) * 1000 = 457/368 * 1000 = 1242 Hz. = Freq. heard by the receiver(Truck driver).
*March 16, 2016*

**Science: Physics**

d = 1000N * 1m/500N = 2 m.
*March 15, 2016*

**Math**

12/4 does not = 8/24. 8/4 = 24/12. So, the ans. is B.
*March 14, 2016*

**physics**

KE = 0.5M*V^2.
*March 13, 2016*

**physics**

V^2 = Vo^2 + 2g*h = 0, h = -Vo^2/2g = -80/-19.6 = 4.08 m. = max. ht. 1. PE = M*g*h/2 = 0.1*9.8*(4.08/2) = 2.0 Joules. 2. PE = 0.1*9.8*4.08 = 4.0 Joules. 3. KE = 0.5M*V^2 = 0.5*0.1*80^2 = 320 Joules.
*March 13, 2016*

**Math**

P = 11/12.
*March 12, 2016*

**algebra**

Width = W feet. Length = W+8 Ft. Width = W+4. Length = W+3. A1 = A2, (W+8)*W = (W+3)*(W+4), W^2 + 8W = W^2 + 4W + 3W + 12, W = 12 Ft., W+8 = 20 Ft.
*March 12, 2016*

**MATH Help!**

C = (2/6)n = (1/3)n.
*March 12, 2016*

**Algebra**

(1,1), (1,2) (1,3), (1,4), (1,5), (1,6). So, there 6 possibilities per side. 6poss./side * 6sides = 36 Possibilities.
*March 12, 2016*

**math**

Bought X eggs @ 18 Cents each. Cost = 18x. (x-8)eggs * 24Cents/egg = 24x-192 = Sale price. Profit = Sale Price - Cost = (24x-192) - 18x = 288 Cents, 6x = 480, X = 80.
*March 12, 2016*

**maths**

x/(x+6), (x+1)/(x+4) = 3/4, 4x+4 = 3x+12, X = 8. 8/(8+6 = 8/14 = 4/7.
*March 12, 2016*

**English**

I hear the mournful wail of millions, whose chains, heavy and grievous yesterday, are to-day rendered more intolerable by the jubilant shouts that reach them. Which definition of rendered is most likely suited for this line? Caused to be a certain nature Melted down Repeated ...
*March 11, 2016*

**English**

To forget them, to pass lightly over their wrongs, and to chime in with the popular theme, would be treason most scandalous. . . Which word is most similar to how chime in is used here? Agree Create Harmonize Resound I have no idea because chime in- means to interject, so ...
*March 11, 2016*

**math**

Multiply Eq1 by 3 and Eq2 by -4 and add: 15x - 12y = -21 -12x + 12y = 84 Sum:3x = 63, X = 21. In Eq1, replace x with 21 and solve for y: 15*21 - 12y =-21, 315 - 12y=-21, -12y = -336, Y = 28.
*March 11, 2016*

**Physics**

Vp + 80 = 325km/h[240o] CCW. Vp + 80 = -162.5-281.5i, Vp = -242.5 - 281.5i = 372km/h[49.3o] S. of W.
*March 10, 2016*