Download Cymath it help you
Answer: 260 downloads of the standard version were there.
Step-by-step explanation:
Let x represent the number of downloads of the standard version.
Let y represent the number of downloads of the high-quality version.
Yesterday, the high-quality version downloaded four times as often as the standard version. It means that
y = 4x
The size of the standard version is 2.9 megabytes (MB). the size of the high-quality version is 4.6 MB. the total size downloaded for the two versions was 5538 MB. It means that
2.9x + 4.6y = 5538- - - - - - - - - - - -1
Substituting y = 4x into equation 1, it becomes
2.9x + 4.6 × 4x = 5538
2.9x + 18.4x = 5538
21.3x = 5538
x = 5538/21.3
x = 260
Answer:
A samira is correct
Step-by-step explanation:
Because she did her own expression right, now she has to solve
Carry out the mult.: f(x) = -[x^2 - 21x + 9x - 189]
Combine like terms: f(x) = -[x^2 - 12x - 189]
Eliminate the brackets [ ]: f(x) = -x^2 + 12x + 189
Identify coefficients a, b and c: a= -1, b=12, c=189
The equation of the axis of symmetry is x = -b/(2a), which here equals
x = -(12)/[2(-1)], or x = 6
This is also the x-coordinate of the vertex. Plug x=6 into the original equation to calculate the y-coordinate.