# Posts by Luke

Total # Posts: 421

**science**

Predict the sign of ( ∆H) in each of the following reactions: NH3 (g) + HCl (g) NH4Cl(s) ∆S = +, ∆G = - Fe (s) + Cu+2 (aq) Fe+2 (aq) + Cu(s) ∆S = +, ∆G = - Cl2 (g) + 2Na (s) 2NaCl (s) ∆S = +, ∆G = -

**chemistry**

sorry, didn't even see that. how does 0.6973 sound?

**Science**

i want to know how you could get electric to an island in the middle of nowhere.

**Physics: Equilibrium and Inclined Planes**

12.8

**Geometry**

okay, thanks anyway.

**Geometry**

How do you divide a hexagon into 9 congruent parts?

**Geometry**

Find the value of z. Then find GE and EH and state whether E is the midpoint of line GH. GH = z + 6. EH =2z-4. GE=z.

**Spanish**

One of the countries in Central America uses Spanish as the official language of the country but also has 23 different Maya groups; each with its own dialect. What country is it?

**math**

what would x^2+y^2-4x+2y=0 (Equation for a cirlce) be in r^2=(x-h)^2(y-k)^2 form? tnx I will start you off... x^2+y^2-4x+2y=0 x^2-4x+y^2 +2y =0 x^2-4x+ 4 + y^2 +2y+ 4 =+ 4+ 4 (x^2-4x+ 4) + (y^2 +2y+ 4) =8

**Math**

Hi how would i solve this?? The equation of the cirlce is x^2+y^2-4x+2y=0. Determine the coordinates of the center and the radius of the circle. What do i do? anyone

**Math**

hi how would we solve a question like this? for the curve with eq'n 2x^2 - x - 1 y= _______________ x^2 - 2x - 3 determina all x- and y-intercepts I assume you meant y = (2x^2 - x - 1)/(x^2 - 2x - 3) both top and bottom factor but there is no advantage gained. However, the...

**Math**

I have no clue how to do this as no values were given and im confused. can someone explain plz? if x^3-y^3=m and x-y=N, express xy in terms of M and N This is one of those pure manipulation problems. you have to know that x^3-y^3 = (x-y)(x^2+xy+y^2) so n(x^2+xy+y^2)=m (x^2+xy+...

**math-factoring**

hi i was reading through the tutorials and havent really understood how to factor out a trinomial like 12x^4 - 5x^2y^2 - 2y^4 what would the 1st few steps be? Do a substitution: let v= x^2 and u= y^2 Now you have... 12v^2 - 5uv - 2u^2 (3v -2u)(4v+u) then go back and put the x ...

**math**

I'm not good at math! I need help with finding a decimal from a fraction. like 1/3, 13/15, 19/32 I can't figure out how to turn it into a decimal! Just divide the numerator by the denominator. Use long division or a pocket calculator. can u help mme because i get f,s ...

**why is noone answering my question?!?!**

A rational function that passes through (0,0) and (4, 8/7) has the x-axis as a horiztonal asympotote. It also has 2 vertical asymptotes x=3, x=-3. I understand that to set it up, it is y= ax+b / (x+3)(x-3). I don't understand how to solve for a and b. Put in the points. ...

**rational functions**

A rational function that passes through (0,0) and (4, 8/7) has the x-axis as a horiztonal asympotote. It also has 2 vertical asymptotes x=3, x=-3. I understand that to set it up, it is y= ax+b / (x+3)(x-3). I don't understand how to solve for a and b.

**rational functions... PLEASE HELPPPPP**

A rational function that passes through (0,0) and (4, 8/7) has the x-axis as a horiztonal asympotote. It also has 2 vertical asymptotes x=3, x=-3. I understand that to set it up, it is y= ax+b / (x+3)(x-3). I don't understand how to solve for a and b.

**chem**

what does coefficients in equations mean, in chemical terms? 2NaCl means we have two molecules or 2 mols of NaCl. Most texts caution us not to use molecules but to stick with the latter part of the definition (moles); however, I don't have any problem with saying, 2H2 + 2 ...

**chemistry 12**

what is the relationship between ka and kb? Kw=ka*kb

**chemistry**

When 1.0 mol of ammonia gas in injected into a o.50L flask, the following reaction proceeds to equilibrium. 2NH3 <--> N2 (g) + 3H2 (g) At equilibrium, 0.30 mol of hydrogen gas is present. a) calculate the equilibrium concentrations of N2 and Nh3. b) what is the value of ...