Andrew has $2.75 in nickels and quarters in his coat pocket. If he has a total of 15 coins, which system of equations could you use to find the number of quarters in Andrews coat pocket? 1)x+y=15 0.5x+0.25y=2.75 2)x+y=2.75 x+y=15
complete factorization y^4-25y^2+144 (^) denotes following number is Power y^4 - 25y^2 + 144 You might try replacing y^2 with x. Therefore your statement becomes: x^2 - 25x + 144 ...which is easier to factor.
solve the system by addition: -5x-9y = -5 x+5y=-15 I've tried this one over and over, but I can't seem to get the right answer. I don't even really know where to start. each time i try to do it, i go about it a little differently
Joint probability density function is: x + y where 0<x<1 and 0<y<1 (0 elsewhere) Find variance of (30x + 25y) Answer is 11.48 --- My calculations Marginal probability density functions (same for x and y): f(x) = x +