The vertex is when x=-b/2a, which is also the line of symmetry.
in this case, b=6, a=3, so x=-6/6=-1
when x=-1. y=3-6-1=-4
another way to do it is to write the equation into vertex form by making a square:
3x²+6x-1
3(x²+2x-1/3)
3(x²+2x+1-1-1/3))
3(x²+2x+1-4/3))
notice the bold part makes a square:
3(x+1)²-4
Either way,
the vertex is (-1, -4)
the axis of symmetry is x=-1
the coefficient of x² is 3, a positive number, so this parabola opens upward. the function has a minimum value of y=-4
the range is all real number larger than -4
Answer:
58.75 degreeF
Step-by-step explanation:
The initial temperature of the Soda = 40degreeF
The temperature outside is steady at 99 degreeF
The temperature of the soda became 50 degreeF after 8 minutes
In 8 minutes, the Soda gained
(50 - 40)degreeF
= 10 degreeF
If the soda gains 10 degreeF in 8 minutes, in 1 minute, it will gain 10/8degreeF
Therefore in 7 minutes, the soda will gain (10/8)*7
= 70/8
= 8.75 degreeF
The expected temperature of soda after an additional 7 minutes = 50 + 8.75
= 58.75degreeF
Answer:
11 1/3 miles
Step-by-step explanation:
