Thursday

April 24, 2014

April 24, 2014

Total # Posts: 8,535

**8th grade algebra**

5x = The # of bikes rented. 2x = The # of scooters renteb 15.50*1.12*5x + 160*1.12*2x = 1600. 86.8x + 358.4x = 1600 445.2x = 1600 X = 3.59 Bikes = 5 * 3.59 = 18 Scooters = 2 * 3.59 = 7.

**8th grade algebra**

5x = The # of bikes rented. 2x = The # of scooters renteb 15.50*1.12*5x + 160*1.12*2x = 1600. 86.8x + 358.4x = 1600 445.2x = 1600 X = 3.59 Bikes = 5 * 3.59 = 18 Scooters = 2 * 3.59 = 7.

**Physics**

The current entering a point is equal to the current leaving the point. Therefore, the current leaving the positive terminal of a battery is equal to the current entering the negative terminal. This is true for the light bulb or any load.

**math**

P = (Po*r*t)/(1-(1+r)^-t) Po = 1598 * 1.05 = $1677.90 r = (15%/12)/100% = 0.0125 = Monthly % rate expressed as a decimal. t = 3yrs * 12mo./yr = 36 Months. Plug the above values into the given Eq and get: P = 2093.94 Monthly Payment = P/t

**Physics**

The brightness increases.

**Science**

Wb = m*g = 17.25kg * 9.8N/kg = 169 N. = Wt of body. Fv = m*g = 169 N. = Force perpendicular to the table. Fs = u*Fv = 0.34*169 = 57.5 N. = Force of static friction.

**physics**

P = F * d/t = F * V = mg * V P=400*9.8 * 0.03m/s = 118 J/s.=118 Watts

**Math**

63miles/22gal. = 2.86 Miles/gal. D = 66gal * 2.86mi/gal = 189 Miles.

**physics**

Rmax = V/I = (500000*.97)/1000=485 Ohms=Max. conductor resistance. Dmax = 485 Ohms / 0.026Ohms/km=18,654 km.

**Physic**

Fp = mg*sin23 = 597.8*2in23=233.6 N.= Force parallel to the hill. Fv = mg*cos23 = 597.8*cos23=550.3 N.= Force perpendicular to the hill. Fk = 72 N. a = (Fp-Fk)/m = (233.6-72)/61=2.65 m/s^2 V^2 = Vo^2 + 2a*d V^2 = (3.5)^2 + 2*2.65*62 = 340.85 V = 18.5 m/s.

**Pre- Algebra**

1. Y = -2x - 4. (1,3). Parallel lines have equal slopes: m1 = m2 = -2. Y = mx + b = 3 -2*1 + b = 3 b = 3+2 = 5 Eq: Y = -2x + 5 2. Y = 3x+3. (1,1). The slope of the line is equal to the negat1ive reciprocal of the slope of the given line. m1 = 3 m2 = -1/3. Y = mx + b = 1 (-1/3)...

**hydromechanic**

Fap-Ff = m*a 124-Ff = m*0 = 0 Ff = 124 N. = Force of friction. u = Ff/Fl = 124/1026 = 0.121 = Coefficient of friction. Fap = Force applied.

**basic math**

The DIGIT in the units(ones) position is 2. TENS Position: 1. HUNDREDS position: 5. THOUSANDS position: 5. TENS of THOUSANDS position: 5.

**math**

The hypotenuse is greater than either of the other 2 sides but less than the sum. Therefore the answer is d. c^2 = 5^2 + 12^2 = 25 + 144 = 169 c = 13.

**Physics**

V^2 = Vo^2 + 2g*h Vo^2 = V^2 - 2g*h. Vo^2 = 0 + 19.6*23 = 450.8 Vo = 21.2 m. h = (0.5Vo)^2-Vo^2)/2g h = ((10.62)^2-(21.2^2))/-19.6=17.2 m.

**MaThS**

A. Y = -2x+1, and Y = -2x+3. m1 = m2 = -2. The lines are parallel, because their slopes are equal. B. x+y/3+5 = 0, and 2y+6x = 1 x+y/3=-5, and 6x+2y = 1. 3x+y = -15, and 6x+2y = 1 m1 = -A/B = -3/1 = -3 m2 = -6/2 = -3 The slopes are equal; therefore, the lines are parallel.

**algebra**

10. 16-9+25 = 32 11. 32/(-7+5)^3 = 32/-8 = -4. 12. 4^3-(2-5)^3 = 64 - (-27) = 91

**math**

Gregg: p + q Coins. Brother: 8p + 4q Coins. Sum = 8p+p + q+4q = 9p + 5q

**math**

1. 0x+6y-5x = 5x+6y. 2. 9x^2+10+4x^2+7 = 13x^2+17.

**algebra**

P1(1,-3),P2(2,4). D^2 = (2-1)^2 + (4+3)^2 = 50 D = 7.07

**Maths**

tan 60o = (Y1+Y2)/X1 = 3000/X1 X1*tan 60 = 3000 X1 = 3000/tan60 = 1732 m. tan 30o = (Y1+Y2)/(X1+X2)=3000/(1732+X2) (1732+X2)*tan30 = 3000 1732+X2 = 3000/tan30 = 5196 X2 = 5196-1732 = 3464 m tan30 = Y2/X2 = Y2/3464 Y2 = 3464*tan30 = 2,000 m. Y1 = 3000-2000 = 1,000 m. = Distance...

**introduction to finance-16**

1. P = Po*(1+r)^n Po = $4,000. r = (4%/100%) = 0.04 n = 1Comp./yr * 5yrs = 5 Compounding periods. Plug the above values into the given Eq and get: P = $4,866.61. 2. P = Po(1+(y-1))*(1+r)^n Y = Length of loan = 5 years. P = 4000(1+4)*(1.04)^5 = $24,333.06

**math**

Eq1: x*y = -84 Eq2: x+y = 5 x+y = 5 y = 5-x In Eq1, replace y with 5-x: x*(5-x) = -84 5x-x^2 = -84 -x^2+5x+84 = 0 Use Quadratic Formula and get: X = -7, and 12.

**Math**

The angles are assumed to be complimentary(sum=90o). DCE + ECF = 90o 4x+15 + 6x-5 = 90 10x + 10 = 90 10x = 80 X = 8 DCE = 4*8 + 15 = 47o

**Mechanics, Waves and Optics**

Wt. of crate=m*g=18kg * 9.8N/kg=176.4 N. Fv = 176.4*cos0 = 176.4 N. = Force perpendicular to the surface. Fk = u*Fv = 0.5 * 176.4 = 88.2 N. = Force of kinetic friction. Fap*cos20-Fk = m*a Fap*0.94-88.2 = 18*0 = 0 0.94Fap = 88.2 Fap = 93.9 N. = Force applied b. Tension = Fap = ...

**physical science**

V = Vo + a*t = 10 m/s. 6 + a*2 = 10 2a = 4 a = 2 m/s^2.

**geometry**

a. RS + ST = RT 8y+4 + 4y+8 = 15y-9. Solve for y. b. Replace y with the value calculated in prob. a.

**Algebra**

P = Po(1+r)^n P = $5000 Po = $3500 r = (4.5%/12)/100% = 0.00375 = Monthly % rate expressed as a decimal. n = 12Comp/yr * T yrs = 12T = The # of compounding periods. P = 3500*(1.00375)^12T = 5000 (1.00375)^12T = 5000/3500 = 1.42857 Take Log of both sides: 12T*Log (1.00375) = Lo...

**Mathematic**

1. 2/(2/3) + 3/4/(4/5). 2/(2/3) + (3/4)/(4/5) = 2*(3/2) + (3/4)*(5/4) = 6/2 + 15/16 = 48/16 + 15/16 = 63/16 2. (2/5)(2/3)/(5/6)/(3/10) = (2/5)(2/3)(6/5)(10/3) = 240/225 = 48/45 = 16/15. The answer cannot be less than one.

**All subjects**

You are welcome! We are glad we can help.

**MatHS**

The angle of inclination is always between 0o and 180o and is measured CCW from the positive x-axis. A. x+y+1 = 0 x+y = -1 Tan A = m = -A/B = -1/1 = -1 Ar = -45o = Reference angle. A = -45 + 180 = 135o. B. 3-2y = 9x 9x+2y = 3 Tan A = m = -A/B = -9/2 = -4.5 Ar = -77.47o A = -77...

**maths**

See previous post: Tue,8-6-13,12:09 PM

**maths**

See previous post: 12:09 PM.

**maths**

Y = 2x Tan A = m1 = 2 A = 63.43o (-1,7/3),(0,2). m2 = Tan B = (2-7/3)/(0+1) = (-1/3)/1 = -1/3. B = -18.43o = -18.43o C = A-B = 63.43 - (-18.43) = 81.9o = Angle between A and B.

**Math**

What is the question?

**maths**

CORRECTION: m1 = m2 = -A/B = 6/2 = 3 Y = mx + b = -1 3*3 + b = -1 b = -10 Eq: Y = 3x - 10

**maths**

(3,-1). -6x + 2y = 1 Parallel lines have equal slopes: m1 = m2 = -A/B = 6/-2 = -3 Y = mx + b = -1 -3*3 + b = -1 b = 8 Eq: Y = -3x + 8

**mathematics**

P(-6,-2). 3x + 2y = 6 m1 = -A/B = -3/2 m2 = -(-2/3) = 2/3 = Negative reciprocal Y = mx + b = -2 2x/3 + b = -2 (2*-6)/3 + b = -2 -4 + b = -2 b = 2. Eq: Y = 2x/3 + 2

**physics**

See previous post.

**physics**

Assuming no wind: Vo*t + 0.5g*t^2 = 1.4 m. 0 + 0.5*1.63*t^2 = 1.4 0.815t^2 = 1.4 t^2 = 1.72 t = 1.31 s.

**algebra**

Yes, post your problem.

**Physics**

h1 = Vo*t + 0.5g*t^2 h1 = -9*18 + 4.9*18^2 = 1426 m Above ground when bag was released. h2 = 9*18 = 162 m.. Above point of release. h = 1426 + 162 = 1588 m. Above ground.

**physics**

A = 3.45 m/s[90o] B = 2.39 m/s[270o] C = V m/s 3.45[90o]+2.39[270]+V = 0 @ the peak of its' trajectory. 3.45*cos90+2.39*cos270+i3.45*sin90+i2.39*sin270 + V = 0 0+0 + 3.45i-2.39i + V = 0 0 + 1.06i + V = 0 V=-1.06i = 1.06 m/s[270o]=1.06m/s[-90o].

**math**

3X5Y/2Y8 = 15x/16. 15x/16 = 1 = The smallest whole number. 15x = 16 X = 16/15 = 1 1/15. According to my analysis, x cannot equal 0,2,4, nor 6.

**science**

The current through all elements of a circuit is the same IF there are no elements in parallel.

**Physics**

tan A = 50m/79m = 0.63291 A = 32.3o East of North = 57.7o CCW. b. Vs = 1.9m/sin57.7 = 2.25 m.[57.7o] = Velocity of swimmer. Vc = 2.25m/s[57.7o] - 1.9[90o] X = 2.25*cos57.7 - 1.9*cos90=1.20 m/s. Y=2.25*sin57.7 - 1.9*sin90 = 0 m/s. b. Vc = 1.20 + i0 = 1.20 m/s =Velocity of the c...

**physics**

See 6:26 PM post.

**physics**

See 5:58 PM post.

**physics**

20*Log(V1/Vo) = 38 db Log(V1/Vo) = 1.9 V1/Vo = 79.4

**physics**

130db/19 = 6.84 db.

**physics**

130db/19 = 6.84 db.

**physics**

a. 10*Log(I1/Io) = 17db Log(I1/Io) = 1.7 I1/Io = 50.1 b. 10*Log(I1/Io) = -32 db Log(I1/Io) = -3.2 I1/Io = 0.00063

**physics**

Vs = 332 m/s @ 0oC. = Velocity of sound. Vs = 332m/s + (22-0)oC*0.6m/s/oC Vs = 332 + 13,2 = 345.2 m/s. @ 22oC. a. d = Vs*t = 345 * 0.8 = 276 m b. d1 = d V*T = Vs*(T+0.8) 3*10^8T = 345(T+0.8) 3*10^8T = 345T+276 3*10^8T = 276 T = 92*10^10^-8 s. d = V*T = 3*10^8 * 92*10^-8 = 276 m.

**math**

2L + 2W = 42 2*11 + 2W = 42 2W = 20 W = 10 L = 11

**Physics**

K = k1 + k2 = 35 + 55 = 90N/cm.

**Math (Triangles)**

A = B = (180-40.33)/2 = 69.83o = Base angles. sinA/a = sinC/c sin69.83/320 = sin40.33/c c*sin69.83 = 320*sin40.33 c = 320*sin40.33/sin69.83 = 220.6 mm Or cosA = 0.5*AB/AC AC*cosA = 0.5*AB AB = 2AC*cosA = 2*320*cos669.83=220.7 mm

**Discrete Mathematics**

Year 1--2013--3^0*500 = 500 Rabbits Year 2--2014--3^1*500 = 1500 Year 3--2015--3^2*500 = 4500 Year n--20xx--3^(n-1)*500 = 100,000 3^(n-1)*500 = 100000 3^(n-1) = 200 (n-1)*Log 3 = Log 200 n-1 = Log 200/Log 3 = 4.82 n = 5.82 or 6 Yrs.

**Discrete Mathematics**

Fx) = 2x + 3*1/x F(x) = 2x + 3/x

**hs math**

P = 249.73/mo * 72mo = $17,980.56 P = (Po*r*t)/(1-(1+r)^-t) = 17,980.56 r = (3.599%/12)/100% = 0.0029992 = Monthly % rate expressed as a decimal. (Po*0.0029992*72)/(1-(1.0029992)^-72)= 17,980.56 Po*0.21594/(1-(1-(1.0029992)^-72)=17980.56. 0.21594Po/0.19396 = 17980.56 1.11332Po...

**physics**

Eq1: 4*t = d Eq2: 5*t = 6 + d In Eq2, replace d with 4t: 5t = 6 + 4t 5t-4t = 6 t = 6 s. In Eq1, replace t with 6: d = 4 * 6 = 24 m.

**physics**

L1 = 0.810 m. Temp. Change = +18o C. T.C. = 1.9*10^-5/C a. T^2 = 4pi^2(L/g) T^2 = 39.4(0.81/9.8) = 3.25653 T = 1.8046 s. b. L2 = L1 + L1*(T.C.)*18 L2=0.81 + 0.81(1.9*10^-5)*18=0.81027702 m. T^2 = 39.4(0.81027702/9.8)=3.25764 T = 1.8049 s. Change in period = 1.8049-1.8046 = 0.0...

**physics**

m1*g = 0.30kg * 9.8N/kg = 2.94 N. L1 = 0.26 m. m2*g = 1.90kg * 9.8N/kg = 18.62 N. L2 = 0.75 m. a. K = (N2-N1)/(L2-L1) K = (18.62-2.94)/(0.75-0.26) = 32 N/M b. (2.94N/32N) * 1M = 0.092 M. L + 0.092 = 0.26 L = 0.26 - 0.092 = 0.168 M.

**General Physics**

Wt. of block=m*g = 4kg * 9.8N/kg=39.2 N. Et = Ek + Ep = 0.5m*V^2 Ek + Ep = 0.5*4*(5.1)^2 = 52 J. 0 + Ep = 52 @ hmax. Ep = 52 @ hmax Ep = mg*h = 52 39.2h = 52 h = 1.33 m. Dist. up ramp = h/sinA = 1.33/sin13= 5.91 m.

**General Physics**

F1 = (0.2m/1m) * 28N = 5.6 N. To stretch spring 0.2 m. Work = F1 * d = 5.6 * 0.2 - 1.12 J. F2 = (0.2m+0.06m)/1m) * 28 N.=7.28 N. Work = F2 * d = 7.28 * 0.26 = 1.89 J. 1.89-1.12 = 0.77 J. to stretch it an additional 0.06 m.

**General Physics**

m*g = 7453 N. m*g = 7453 N. Fp = 7453*sin25.9 = 3256 N. = Force parallel to incline. Fap = Fp = 3256 N. = Force applied. Work = F * d = 3256 * 4.04 = 13,152 J. fp =

**geometry**

<1 = <2 = 4x-9 = 63o. 4x-9 = 63 4x = 63+9 = 72 X = 18o. The value of 9 is 9.

**physics**

Vo = 60km/hr = 60000m/3600s = 16.67 m/s. V^2 = Vo^2 + 2a*d a = (V^2-Vo^2)/2d a = (0-(16.67)^2)/60 = -4.63 m/s^2. Wt. of car = m*g = 15000 N. mass = 15000/9.8 = 1531 kg F = m*a = 1531 * -4.63 = -7.1 N.

**physics**

a=(V-Vo)/t = (-48.4--43.8)/1.08=-85.37 m/s^2. F = m*a = 0.148 * -85.37 = -12.6 N.

**Math**

3^2 + 3 = 12. Units digit = 2.

**calculus**

V^2 = Vo^2 + 2g*h h = (V^2-Vo^2)/2g h = ((190)^2-(30)^2)/64 = 550 Fi.

**compound intrest**

T = 365 + 57 = 422 Days. r = (3.5%/365)/100% = 9.58904*10^-5 = Daily % rate expressed as a decimal. I = Po*r*T I= 32000*0.00009589*422 = $1294.90

**Physics**

Vc = 81000m/3600s = 22.5 m/s. = Velocity of car. F = ((V+Vr)/(V+Vc)))*Fh = 958Hz. ((345+22.5)/(343-22.5))*Fh = 958 367.5Fh/322.5 = 958 1.140Fh = 958 Fh = 841 Hz. = Freq. of horn.

**Physics**

A. h = Vo*t + 0.5g*t^2 = 0.481 m. 0 + 4.9t^2 = 0.481 t^2 = 0.09816 t = 0.313 s. Each ball. B. V = Vo + g*t V = 0 + 9.8*0.313 = 3.07 m/s. Each ball.

**algebra**

2^3*sqrt(18)/6 = 8*sqrt(9*2)/6 = 8*3*sqrt(2)/6 = 24*sqrt(2)/6 = 4*sqrt(2). sqrt means square root.

**science**

See previous post.

**science**

A = 5m[240o] B = 2.5+6i C = -2.5i X = 5*cos240 + 2.5 = 0 Y = 5*sin240 + 6 - 2.5 = -0.83 D = 0-0.83i = 0.83m[-90o].

**general physics**

V^2 = Vo^2 + 2g.h Vo^2 = V^2-2g.h Vo^2 = 0-(-19.8)*190sin13 = 837.7 Vo = 28.9 m/s.

**dynamics**

See 10:35am post.

**Dynamics**

Ek = 0.5m*V^2 *h - = 750 * 6^2 = 27,000 J. Wt. = Fg = 1500kg * 9.8N/kg = 14,700 N. Ep = Fg * h = 27000-Fk*d 14700*5*sin20 = 27000-Fk*5 25138.5 = 27000-5Fk 5Fk = 27000-25138.5 = 1861.5 Fk = 372 N.

**dynamics**

V^2 = Vo^2 + 2g*h h = (V^2-Vo^2)/2g h = (0-625)/-19.6 = 31.89 m. NOTE: V = 0 @ max. Ht.

**general physics**

Di + Db = Dsw 917 + Db = 1025 kg/m^3 Db = 108 kg/m^3 = Density of the bear. Mass of bear = 6.76m^3*108kg/m^3=730 kg Wt. of bear = 730kg * 9.8N/kg = 7154 N.

**science**

CORRECTION: Ek = 84.672 J.

**science**

V^2 = Vo^2 + 2g*d Vo^2 = V^2-2g*d Vo^2 = 0-(-19.6*1.2 = 23.52 Vo = 4.85 m/s. Ek = 0.5m*Vo^2 = 3.6*(4.85)^2 = 11.76 J. vo^2

**MATH**

h = 125-5t^2 = 0 -5t^2 + 125 = 0 t^2 - 25 = 0 (t+5)(t-5) = 0 t = -5 t = 5 s. V = g*t = 9.8 * 5 = 49 m/s.

**physics**

Vs = 25 m/s = Velocity of the source. F = 260 Hz(NOT 26Hz). Fo = 240 Hz. Vr = Velocity of the receiver(person) F = (V+Vr)/(V-Vs)*Fo = 260 Hz. (V+0)/(V-25)*240 = 260 240V/(V-25) = 260 240V = 260V - 6500 -20V = -6500 V = 325 m/s.

**Math**

P = (Po*r*t)/(1-(1+r)^-t) Po = $81,000. r = (9%/12)/100% = 0.0075 = Monthly % rate expressed as a decimal. t = 25yrs. * 12mo/yr. = 300 Months. Plug the above values into the given Eq and get: P = $203,924.72 Monthly Payments = P/t Monthly Int. = (P-Po)/t. Monthly Prin. = (P/t)...

**physics/science**

See previous post.

**physhcs**

Xc = 1/W*C = 1/314.2*3*10^-6 = 1061 Ohms Z = R-jXc = 500 -j1061 = 1173[-64.8o]. 1. I = V/Z=12/1173[-64.8o]=0.01023[64.8] 2. Vc= I * Xc = 0.01023[64.8]*1061[-90o]= 10.85 Amps.[-25.2o] 3. A = -25.2o 4. P = I^2*R = (0.01023)^2 * 500= 0.0523 W. 5. Pf = cosA = cos(-64.8) = 0.426

**phys ics**

b. V = (0.243/0.335) * 28m/s = 20.3 m/s.

**physics**

Circumference=pi*2r=3.14*0.67=2.1=2.1 m. Va = 24.1m/s * 6.28rad/2.1m=72.1 rad/s.

**physics**

d = 0.5g*t^2 = 5.95 m. 4.9t^2 = 5.95 t^2 = 1.21 s. t = 1.10 s. 2.55rev/s * 1.1s = 2.8 revs.

**physics**

a. 28.9rad/s * 1rev/6.28rad = 4.60 rev/s. t = (13.6/4.60) * 1s = 3.0 s. b. V = Vo + at = 0 When @ rest. 28.9 + a*3 = 0 3a = -28.9 a = -9.63 rad/s^2.

**physics**

a. d = 2870rev * 6.28rad/rev = 18,024 rad. t = 18,024rad/131rad/s = 138 s. V = Vo + a*t = 131 rad/s Vo + 0.170*138 = 131 Vo = 131-23.4 = 108 rad/s. b. t = 138 s.

**physics**

V = Vo + at = 4.4 rad/s. 0 + 4.2t = 4.4 t = 4.4/4.2 = 1.05 s.

**physics**

d1 + d2 = 2pi rads = A complete circle. V1t + V2t = 2pi 2.46*10^-3 + 7.91*10^-3 = 6.28 10.37*10^-3t = 6.28 t = 606 s.

**Math**

See previous post.

**Math**

See previous post.

**Math**

Eq1: x^2 + y^2 = 34 Eq2: x + y = 2 x + y = 2 Y = 2 - x In Eq1, replace Y with 2 - x. x^2 + (2-x)^2 = 34 x^2 + 4 - 4x + x^2 = 34 2x^2 -4x + 4 = 34 2x^2 -4x - 30 = 0 Divide both sides by 2: x^2 - 2 - 15 = 0 (x+3)(x-5) = 0 x+3 = 0 X = -3. Y = 2- x = 2-(-3) = 5 x-5 = 0 X = 5. Y = ...

**physics**

Wt. = (6.0/1.0)^2 * 45.8 = 1649 N.

**Elementary mechanics**

My answer is the Rise Time or time to reach max. height. R = Vo*cosA * (Tr+Tf) Tr = Tf. Therefore, R = Vo*cosA * 2Tr. Tr = Rise time. Tf = Fall time. Vo*cosA = Hor. component of initial velocity.

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