<em>while the two were at the movies Katie spent $40.00</em>
Average:
4.4 / 3 = 1.4666666666667
Count:
3
Sum:
4.4
Average:
4.4 / 3 = 1.4666666666667
Count:
3
Sum:
4.4
Answer:
g
Step-by-step explanation:
Answer:
Wind speed = 30 mph
Plane speed = 270 mph
Step-by-step explanation:
Given that :
Distance = 600 miles
Let speed of airplane = a ; speed of wind = b
Net speed ; with wind = a + b
Net speed against wind = a - b
Time taken with wind = 2 hours
Time taken against wind = 2.5 hours
Recall :
Speed = distance / time ; distance = speed * time
(a + b) * 2 = (a - b) * 2.5
2a + 2b = 600
a + b = 300 - - - (1)
a = 300 - b
2.5a - 2.5b = 600
a - b = 240 - - - (2)
300 - b - b = 240
300 - 2b = 240
-2b = - 60
b = 30
a = 300 - 30
a = 270
Wind speed = 30 mph
Plane speed = 270 mph
The answer is down the page under ANSWER. here is a quick explanation first.
okay, i assume your equation is actually like this:
minus x squared plus 4 x minus
note: the proper way to type this electronically is: -x^2 + 4x - 2.
The equation you gave is known as a quadratic equation.
if you think about it, the generic (general) way of writing this quadratic equation is:
ax^2 + bx + c
a, b and c are just numbers
eg.
2x^2 + 7x + 4
looking at the general equation above
a is 2
b is 7
c is 4
you can put negatives in as well, to find out a, b and c
eg
-2x^2 - 6x - 12
so, what is a b and c?
a is -2 (must say its negative)
b is - 6 (must say negative)
c is - 12 ( again, remember its a negative number)
ANSWER
IF YOU JUST WANT THE ANSWER.
THE DISCRIMINANT IS:
4 squared minus (4 times -1 times -2)
this is 16 - 8
solution of discriminant is 8
explanation:
so, now we cleared that up.
in any quadratic equation ( like the equation you gave), the discriminant is (in general)
b2 - 4ac
use this to solve it for any quadratic equation for the discriminant