Answer:
The y-intercept will always be the vertex of the function.
Step-by-step explanation:
The functions with the following form 
are quadratic equations and have a parabolic form, which means the have a vertex. The x coordinate of the vertex is given by the following expression 
. When b is equal to zero, the vertex of the function will always be the y-intercept, therefore the correct answer is the third one.
Answer:
8/15
Step-by-step explanation:
Pitch = rise/half-span = (8 ft)/(1/2×30 ft) = (8 ft)/(15 ft) = 8/15
Answer:
3n + 21
Step-by-step explanation:
3(n + 7)
3n + 21
width (w) = w
Length (L) = 3w + 4
Area (A) = L x w
25 = (3w + 4)w
25 = 3w² + 4w
0 = 3w² + 4w - 25
w = 
w ≈ 2.3, w ≈ -3.6 (width cannot be negative!)
w ≈ 2.3
Length (L) = 3w + 4 = 3(2.3) + 4 = 6.9 + 4 = 10.9
Answer: width=2.3, Length=10.9
