The answer is 3.00-0.22=2.78
Answer:
Step-by-step explanation:
Your equation makes no sense.
I will ASSUME you mean
y = -x² - 2x + 3
which can be factored
y = (x + 3)(-x + 1)
x intercepts occur when y = 0
0 = (x + 3)(-x + 1)
which means either
x + 3 = 0
x = -3
or
-x + 1 = 0
x = 1
x intercepts are (-3, 0) and (1, 0)
The vertex will occur halfway between these point
x = (-3 + 1) / 2 = -1
so vertex = y = -(-1)² - 2(-1) + 3 = 4
(-1, 4)
1 gallon =128
1/2 gallon =64
128 x 5 (gallons)= 640 + 64 (1/2 gallon)= 704
so your answer is 704
