# Posts by Scott

Total # Posts: 3,269

**algerba math**

multiplying by 3 it's a 3 power series ... 3^2, 3^3, 3^4, ...

**math**

absolute = gauge + ambient ambient is usually atmospheric ... 14.7 psi

**Math**

subtracting the equations ... 0 = 5/2 x - 5 solve for x

**mechanicle engineering**

momentum is conserved 50000 * 30 = (50000 + 10000) * v ...1500000 = 60000 v ... v = 25 initial KE ... 1/2 * 50000 * 30^2 final KE ... 1/2 * 60000 * 25^2

**Math**

2011th term has had 2010 threes added to the 1st term, -4

**Chemistry**

in addition to being solid, ice floats the added buoyancy helps to support a person's weight

**Science - Climate change**

yes, water has a higher heat capacity (specific heat) than land also, solar energy (radiation) can penetrate deeper into the water the warmer air (over the land) is less dense and is displaced upward by the cooler air flowing in from over the water...sea breeze

**geometry**

it has to be long enough so that combined with the 4 m side, it can reach the end of the 9 m side to form the triangle it has to be short enough so that the 9 m and 4 m sides can close up the triangle (9 - 4) < s < (9 + 4)

**math**

that will work

**Science**

the masses and volumes are the same, so the densities would be also there are more moles of H2, so it has a higher pressure just as you surmised

**Science**

looks good

**Chemistry Basic**

1.00 g Li ... plus ... 2.73 g F divide by their respective molar masses to find the molar ratio of the empirical formula

**Physics**

so it's a water cube? ice has too low a density

**Biology question pH**

pH is logarithmic a change of 2 in pH means a hundred times change in the concentration of H+ ... 10^2 = 100 10^4 = 10000

**Precal**

[ln(7) / 2] x = ln(5) - [ln(5)] x x = ln(5) / {[ln(7) / 2] + ln(5)}

**Algebra**

n + 2s = 57 n + s = 18 subtracting the equations will give you s substitute back to find n

**Physics**

look at the kinetic energy for rolling up ... the steeper the ramp, the faster the KE becomes gravitational PE same holds true for rolling down, except the energy goes in the other direction

**math**

FOIL the binomials -16 - 24i + 6i + 9i^2 ... i^2 is (?-1)^2 collect like terms -25 - 18i

**Math**

SA is proportional to the square of the height V is proportional to the cube of the height

**Math**

the volumes of the model engines are proportional to the cubes of the scale factors

**Math**

it saves having to write out a lot of zeros, reducing the chance for error (and writer's cramp) one digit to the left of the decimal point ... the magnitude expressed as a power of ten 371 = 3.71x10^2 ... or ... 3.71E2 ... E describes the exponent of ten .00263 = 2.63x10^-...

**physics**

watch your sig figs you're mixing g and kg also , water density is 1000 kg/m^3 ... or 1 g/cm^3 V = 3300 g / 2.75 g/cm^3 convert V to m^3 and use 9.81 for g ... Fb will be in Newtons

**arithmetic progression**

2[(5 * 3) + 10d] = (8 * 3) + 28d

**Probability and Statistics**

another binomial p (prefer A) = .85 = (P) p (not prefer A) = .15 = (N) (P + N)^19 = 19C17 P^17 N^2 ... = 171 * .85^17 * .15^2

**Probability and Statistics**

this is a binomial problem probability of hit (h) = .193 probability of no hit (n) = 1 - .193 = .807 at least 2 means not zero and not one (n + h)^7 = n^7 + 7 n^6 h... p(h ? 2) = .807^7 + (7 * .807^6 * .193)

**Geometry**

no figure?

**math**

looks good

**maths**

(4C3) * (5C3) * (6C3)

**algebra math, 8th grade**

the 1st number in the parentheses is the x-value (left/ right or horizontal) the 2nd number in the parentheses is the y-value (up/down or vertical) final position ... [(-2+1),(-5+3)]

**physics**

constant velocity (not accelerating), means the the thrust equals the resistive force

**Algebra2**

sorry you're stuck ... we can help need examples

**physics**

looks good

**Freshman Algebra 1 Honors**

p = 303146000 (1 + .0091)^(2017-2009) or ... p = 303146000 e^[.0091(2017-2009)] v = 125000 (1 - .15)^10

**Science**

molarity is moles of solute per liter 1L of solution has a mass of ... 1010 g mass of H2O2 is ... 1010 * .152 g divide H2O2 mass by H2O2 molar mass to find the molarity

**physics**

the ratio of the areas is the square of the ratio of the radii

**Algebra I**

I answered this before you start with -4 then add 3 , 2010 times -4 + 6030 is the 2011th term

**precalculus**

looks good

**physics**

moon's gravity provides the centripetal force for the orbit m v^2 / r = G M m / r^2 orbital velocity ... v = 2 ? (1500 + 550) * 1000 / (48 * 3600) r = (1500 + 550) * 1000 meters ... G = 6.67E-11 M = v^2 r / G kg

**Math**

4C2 ways to get two aces 52C2 ways to get two cards 4C2 / 52C2 = ?

**math**

use a table to find the z-score for the upper 15% cutoff score = 280 + [(z-score) * 20]

**Math**

210000 - 185000 = 25000 25000 / 20000 = 1.25 s.d. above the mean ... this is the z-score use a table to find the fraction above this z-score

**physics**

answered at 6:13

**Algebra**

gravity provides a force of attraction between masses a force acting on a mass causes it to accelerate the function [s(t)= -1/2 gt^2 + vt + h] describes the height (s) relative to time (t) of a mass (object) in freefall ... g is the gravitational acceleration ... v is the ...

**Math**

[(400 - 360) / 400] * 100%

**Math**

yes

**Math**

try moving the decimal point 1/2 = .5 = 50%

**Algebra I**

-4 + (3 * 2110)

**Math**

p is the population 5 yrs ago you do know how to work a calculator, yes?

**Math**

3104 = p (1 + .05)^5 log(3104) - 5 log(1.05) = log(p)

**Math**

line would go to the left Z values are less than 8

**Math**

yes

**GEOMETRY**

m?G = m?C 180º - m?B - m?C = m?A

**Math**

a + s = 450 200a + 150s = 14400 solve the system by using substitution or elimination

**algebra**

they each do a fraction of the task, based on their individual times ... the fractions sum to one (the whole task) t/21 + t/28 + t/48 = 1 ... LCD is ... 21 * 16 16t/336 + 12t/336 + 7t/336 = 336/336 35t = 336

**physics**

gravity provides the centripetal force m g = m v^2 / r ... v^2 = r g = 22 * 9.8 answer is in m/s

**algrebra 2**

g(x) substitutes for x in f(x) ... 2(4x + 2) - 2 = 8x + 2

**Math**

probability event not happening ... 1 - p

**algebra**

area = x * y x + 2y = 45 ... x = 45 - 2y substituting ... a = 45 y - 2 y^2 ymax = -b / 2a = -45 / (2 * -2) = 11.25 x = 22.5 a = 22.5 * 11.25 = 253.125

**Intermediate Algebra**

the marked-up price (m), is 33% more than the publisher's price (p) m = p + .33 p ... 75 = 1.33 p

**algebra 1**

if you solve the 2nd equation for y ... resulting in the slope-intercept form you will see that the slopes are negative-reciprocals of each other

**algebra 1**

two lines can intersect without being perpendicular ... like an X

**Algebra I**

B would be correct if it had a decimal point ... .63 the others aren't even close

**geometry**

check the naming of the angles ... the middle letter is the vertex ... ACB AND ACD can't be in the same triangle

**Math**

it takes her twice as long to go half as far so she walks a quarter as fast as she rides w = (d/2) / 2t = 1/4 d/t r = d/t

**math**

(60 * .6) + (x * 0) = (60 + x) * .5 (60 * .6) + (x * .3) = (60 + x) * .5

**Physics**

the net accelerating force is the difference in the weights (gravitational force) of the two masses a = f / m = (120 N - 80 N) / 20 kg find tension by looking at the smaller mass ... net force required for acceleration T - W = 8 kg * 2 m/s^2 ... T - 80 N = 16 N

**Calculus**

you used degrees, yes? 1051? implies radians ... so the answer would be ?

**Mathematics (Quadrilaterals)**

the angles sum to 360º 360 - 110 - 70 = 180 4n + 5n = 180 find n , then find the two angles (4:5)

**Maths**

(185 + 240) / (15 + 20) = S m/s 1000 m in a km ... 3600 s in an hr m/s * 3600 s/hr / 1000 m/km = km/hr

**Calculus**

continuous growth ... p e^(rt) 2.8E9 = 6E8 e^(300r) ln(28/6) = 300 r ... solve for r 2.5E10 = 6E8 e^(rt) ... solve for t

**Math Help!!**

y = -1/49 x the slope of the perpendicular is ... -(-1/49) = 49 the 1st derivative is the slope of the tangent ... dy/dx = 14x + 7 14x + 7 = 49 find x, then find y from the original function

**physics**

their brightness ratio is the ratio of the inverse of the square of their distances bP / bQ = (dQ / dP)^2

**physics**

f = m * a ... answer is in Newtons

**Algabra**

division by zero is undefined

**physics**

a. acceleration = speed / time ... 40 / 5.0 b. (average speed) * time ...[(0 + 40)/2] * 5.0

**math**

{[1 + (.2351 / 365)]^365} - 1

**physics**

it's an inverse square relationship B appears 16 times brighter ... 4^2

**Algebra**

6400 * [1 + (.08 * 9/12)]

**math**

3 in = 5 mi squaring ... 9 in^2 = 25 mi^2 a = (45/9) * 25 mi^2

**Math**

y + 5 = -2/5 (x + 3)

**Algebra**

i = ?-1 ... i^2 = -1

**Algebra**

(x + 1 - 4i)(x + 1 + 4i) x^2 + x + 4ix + x + 1 + 4i - 4ix - 4i - (4i)^2

**Math**

the area of the round pizzas is equal to the rectangular pizza 2 ? r^2 = 40 * 60 ... r^2 = 1200 / ? diameter = 2 r

**Science**

I think you are right lighter fish are less visible than darker fish in the clearer water

**Algebra pleaseee helppp**

C(54,11) are duplicates

**Math**

arithmetic means that the difference between any two consecutive elements is always the same any two numbers next to each other always have the same difference

**Algebra**

16. b^2 - 4 a c = 144 ... a perfect square ... the roots (intercepts) are unequal integers 17. the equation of the axis of symmetry is the average of the intercepts ... a.o.s. ... x = (8 - 4) / 2

**math**

"so the answer is 9,4?" ... no Q = [(Mx + 9),(My + 4)]

**math**

Q is as far from M , as M is from P 9 in the x-direction ... 1 - -8 ... Qx = Mx + 9 4 in the y-direction ... 7 - 3 ... Qy = My + 4

**math**

the x distance is ... 18 - 2 = 16 2/5 * 16 = 32/5 = 6.4 Ax + 6.4 = 8.4 the y distance is ... 12 - 6 = 6 2/5 * 6 = 12/5 = 2.4 Ay + 2.4 = 8.4 partition point ... (8.4,8.4)

**Maths**

cross section ... (? / 4)[(do)^2 - (di)^2] volume = cross section * length mass = volume * density weight = m g

**Algebra**

the center of the circle is the average of the intercepts ... (1 - 7) / 2 = 4 ... center at (0,4) the radius is the distance from the center to one of the intercepts ... 7 - 4 = 3 the general circle equation is ... (x - h)^2 + (y - k)^2 = r^2 ... center at (h,k) , radius = r

**Math**

9 * 8 = 72 ... 72 + 5 = 77

**Science**

displacement means how far from where you start once around brings you back to where you start

**Science - Physics**

power = (weight * height * reps) / time watts = (50 * 9.8 * .5 * 40) / 60

**algebra 1**

slope = change in y / change in x

**physics**

angular ... 2.55 rad / 2.30 s

**physics**

one lap (circle) is 2? radians 5/2 * 2? radians in 3.0 min (180 sec) angular speed is rad/s or rad/min

**Math**

d/12 + 1/15 = d/10 - 1/10 ... 60 is LCD 5d + 4 = 6d - 6

**Geometry**

got the right slope point-slope ... y - 7 = -1/2 (x + 4) equation looks good