23 can round to 20 and 21 can also round to 20 so all u do is 20x20=400 so 400 is your estimated answer
The absolute minimum of this graph is y=-10
Answer:
Rate of change of y is 
Step-by-step explanation:

: $55
:
Cost first 3 lines: $11 per line
Cost per additional line: $5
We are interested in 5-line ad, we place 3 lines or less, then we have to pay $11 per line in the ad.
Cost 5-lines = number of lines x cost per line
x = 5 x 11
55
Axis of symmetry: x=1
Vertex: (1, -24)
Explanation:
6x²-12x-25=-7
6x²-12x-18=0
a=6, b=-12, c=-18
Formula of axis of symmetry: x=-b/2a
x=-b/2a
x= -(-12)/2(6)
x= 12/12
x= 1
Vertex: (1,?)
Sub x= 1 into the equation,
6(1)² - 12(1) - 18 = y
6 - 12 - 18 = y
y = -24