Question 906229
let x = number of standard quality downloads at 2.9 MB.
let y = number of high quality downloads at 4.4 MB.


x + y = 1010
2.9x + 4.4y = 3424


these 2 equations need to be solved simultaneously either by graphing or by substitution or by elimination or by matrix methods which are similar to elimination.


we'll do elimination.


mjultiply both sides of the first equation by 2.9 to get:


2.9x + 2.9y = 2929
2.9x + 4.4y = 3424


subtract the first equation from the second eqution to get:


1.5y = 495


divide both sides by 1.5 to get y = 330


since x + y = 1010, this means that x has to be equal to 680 because 680 + 330 = 1010.


since you used the first equation to solve for x, then use the second equation to confirm your solutions are correct by replacing x with 680 and y with 330 in that equation to get:


2.9x + 4.4y = 3424 becomes 2.9*680 + 4.4*330 = 3424 which becomes 1972 + 1452 = 3424 which becomes 3424 = 3424, confirming your solution is correct.


your solution is:


number of high quality downloads was 330.