I already posted a thread about a "physics" (although I am actually in basic college algebra) but I have a few more that I need help with. 1) A jumbo chocolate bar with a rectangular shape measures 12 cm in length, 7cm in width and 3 cm in thickness. Due to escalating costs of cocoa, management decides to reduce the volume of the bar by 20%. To accomplish this reduction, management decides that the new bar should have the same 3 cm thickness but the length and width of each should be reduced an equal number of centimeters. What should the dimensions of the new candy bar be? ~Now I know that the formula for volume is lwh. So I took the original measurements 12 x 7 x 3 and got 252. I reduced that by 20% which would be 252-50.4= 201.6 to get the new volume of the reduced bar. Now I know that the thickness is going to stay the same so I think the new equation would be 201.6=lw x 3. I need to make sure that the length and width get reduced the same amount so I have to make sure that they stay 5 cm apart (if original l=12 and w=7 12-7=5cm) so I made the equation say 201.6= w+5 x w x 3 (x's are multiplication symbols by the way) but now what do I do..do I subtract 5 from both sides and make the w's w^2 and then divide both sides by 3 and square root the answer to get w? And then once I know that I can find l? I don't know what to do from here! 2)Find k such that the equation x^2 - kx +4 =0 Ok so I subtacted 4 from each side to get x^2 - kx= -4 Now I am horrible at these so I am probably way off but then I divded both sides by x....so that I had x-k = -4 over x (I don't know how to type fractions, sorry!) but I had no idea what to do from there...I am supposed to only keep a constant on the right correct? So moving x over seemed wrong to me, but with only one given number in an equation I don't know what to do. I guess that is it for now, I have more but maybe I can do them once I know how to do these ones. Thanks guys!