D BECAUSE OF THE POSITIVE 2
The answer would be 20 or 9
The formula is L = 2 pi r * (angle measure / 360). We have everything we need to solve this, the angle is 90 and the radius is 12: L = 2 pi (12) (90/360). Do the work inside the parenthesis first to get : L = 2 pi (12)(.25). Solving for L: L = 6pi
System of Linear Equations entered :
[1] 5x - 6y = 7
[2] 6x - 7y = 8
Graphic Representation of the Equations :
-6y + 5x = 7 -7y + 6x = 8
Solve equation [2] for the variable x
[2] 6x = 7y + 8
[2] x = 7y/6 + 4/3
// Plug this in for variable x in equation [1]
[1] 5•(7y/6+4/3) - 6y = 7
[1] - y/6 = 1/3
[1] - y = 2
// Solve equation [1] for the variable y
[1] y = - 2
// By now we know this much :
x = 7y/6+4/3
y = -2
// Use the y value to solve for x
x = (7/6)(-2)+4/3 = -1
Hi there!
Many things we do in everyday life have a variety of ways we can go about accomplishing them, but we most often choose the most practical and efficient method.
Efficiency saves time and prevents over-complication, which may lead to errors.
We might need to identify the specifics of the task and its circumstances to be able to determine the most efficient method to do it.
Solving a quadratic equation, we also must think about the most efficient method that can lead us to the correct answer. And doing so, we must identify the circumstances of the equation; Can it be solved by factoring? Is it easy to factor? What form is this quadratic equation in?
For example, let's say we're given the equation (x-1)(x+2)=0. This is an equation in factored form. In these kinds of scenarios, we can <em>easily</em> solve by setting each term equal to 0 (the Zero Product Property). This is the <em>most efficient </em>method:
x-1=0 --> x=1
x+2=0 --> x=-2
I hope this helps!