Answer:
There are two real roots because b²>4ac
in the equation, b²= 9² = 81.
4ac = 4×-4×-12= 72
Answer:

Step-by-step explanation:
We have,
Radius of the circle is 12 cm
Arc length, l = 21 cm
It is required to find the central angle of the circle. The formula for the length of an arc of a circle is :

is central angle

So, the angle at the centre of the circle is
.
The percentage increase; you'll need to take the new value and subtract it by the old value.
16 - 13 = 3
Next, you'll divide 3 by the original value.
3 ÷ 13 = 0.23
And multiply by 100
The percentage increase of friends is 23%
Using the given formula T = LS
And given the time is 3 minutes (3 x 60 = 180 seconds)and the speed is 4-1/2 inches per second:
180 = L x 4-1/2
Solve for L by dividing both sides by 4-1/2:
L = 180 / 4-1/2
L = 40
The length should be 40 inches.
Answer:
600 cm^2
Step-by-step explanation:
The side length of one of the faces is 10 cm
The length of a side is generally noted as s.
In this problem s = 10
Area of a cube face = s^2
So the area of one face of a cube = s^2 = 10^2 = 10*10 = 100
There are 6 faces on a cube.
Area = 6 * 100 = 600