Where is the vertex of the equation?y = x2 – 18x + 80

vertex = (9, - 1 )

Step-by-step explanation:

Given a quadratic in standard form, y = ax² + bx + c : a ≠ 0

Then the x- coordinate of the vertex is

= -

y = x² - 18x + 80 ← is in standard form

with a = 1 and b = - 18, thus

= - = 9

Substitute x = 9 into the function for corresponding value of y

y = 9² - 18(9) + 80 = 81 - 162 + 80 = - 1

Vertex = (9, - 1 )

i think it is 70

step-by-step explanation:

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.