7th grade math
Oh my gosh, I'm dying of laughter. Jessie, why don't you stop being a little snot and pay attention in class. 26/143 = x/100 You cross-multiply 26*100=143*x 2600=143*x Then you find x, as Ms.Sue tried so nicely to explain to you, by dividing 2600 by 143 (2600/143) whic...
algebra ll
y = x^2 + 9x y = x*(x+9) at y = 0, x*(x+9)=0 This is only possible when x = 0 or -9.
Chemistry
Total is 100%, so assuming x is the fraction of Cu-63, (1-x) is the fraction of Cu-65. Atomic weight is the (weighted) average of all isotopes. Therefore you have: x*62.93 + (1-x)*64.93 = 63.55 x = 0.69. So you have 69% Cu-63 and 31% Cu-65.
geometry
The spacing got messed up... The first column is for P Second is for Q Third is for ~Q and the last is for P => ~Q
geometry
I'm assuming you're trying to say "if p, then not q". For this, the table should go like this: P Q ~Q P => ~Q T T F F T F T T F T F T F F T T
math
The slope between two points is: slope = (y2 - y1)/(x2 - x1) (0.6,0.5) = (x1,y1) and (0.2,-0.3) = (x2,y2). Plug in and solve for the slope.
physics
Frequency = (speed)/(wavelength) However! The speed of a wave is constant for a given medium (ex. air, water). Therefore doubling frequency halves the wavelength, but keeps speed constant.
physics
Same concept as for this question: "Doubling the frequency of a wave source doubles the speed of the waves"
physics, please help me, this question is hard
a. Vf^2 = Vi^2 + 2*a*d solve for Vi given Vf = 0 (speed at max height is 0), a = -9.81 m/s^2 and d = 3m. b. Once you know Vi, you can use Vf = a*t + Vi and solve for t. (once again, Vf = 0 since you're only considering the path of the ball from the top of the building to m...
math
The difference of cubes formula is: x^3 − y^3 = (x − y)*(x^2 + xy + y^2) Your x is x in this case and y = 8 (2^3). So you get: x^3 - 2^3 = (x - 2)*(x^2 + 2x + 4).
For Further Reading
