Answer:
90 calories in a banana.
Step-by-step explanation:
O = B - 20 where O is the number calories in an orange and B is a that in banana.
Also 7B = 9O
From the above O = 7B / 9 so substituting in the first equation:
7B / 9 = B - 20
7B = 9B - 180
2B = 180
B = 90.
As it has a maximum value the coefficient of x^2 will be negative
The vertex will be at (-8,2) so in vertex form it is
y = a(x + 8)^2 + 2
and as it passes through (-7,-1) we have:
-1 = a(-7+8)^2 + 2
-1 = a + 2 so a = -3
answer is y = -3(x + 8)^2 + 2
in standard form this is y = -3x^2 -48x - 190
B is 747.7 ..................
U and 2 friends....so it will be split 3 ways
1st day : 93
2nd day : 75
3rd day : 108
for a total of : 93 + 75 + 108 = 276
split 3 ways.....276/3 = $ 92 per person <==