Answer:
87.5
Step-by-step explanation:
By completing the square,
y
=-14x^2+70x
=-14(x^2-5x)
=-14(x-5/2)^2+175/2
the max. height=175/2
i.e. 87.5
Answer:
5x + 3y = 95
8x + 6y = 170
x = 10 ; y = 15
Step-by-step explanation:
Let :
x = pack of juice boxes
y = pack of water bottles
Pack of juice box = $5
Pack of water bottles = $3
Amount of money spent :
5x + 3y = $95
Number of drinks purchased :
8x + 6y = 170
Using both equations ;
5x + 3y = 95 - - - (1)
8x + 6y = 170 - - - (2)
Multiply (1) by 6 and (2) by 3
30x + 18y = 570
24x + 18y = 510
Subtract :
6x = 60
x = 60 / 6
x = 10
Put x = 10 in (1)
5(10) + 3y = 95
50 + 3y = 95
3y = 95 - 50
3y = 45
y = 45 / 3
y = 15
x = 10 ; y = 15
Answer:
(-3, 3)
Step-by-step explanation:
Substitute for y:
x+6 = -2x -3
3x = -9 . . . . . . . add 2x -6 to both sides
x = -3 . . . . . . . . divide by 3
y = (-3) +6 = 3 . . substitute for x in the first equation
The solution is ...
(x, y) = (-3, 3)
Hello :D
To work this out you need to round the numbers to a whole number.
19.9 = 20
5.8 = 6
20 x 6 ≈ 120
I hope this helps :)
