I worked them out separately if I'm correct, then the order is:
x+5y=-2
x+5y=4 These are Inconsistent
y=3x+4
-2x+y=4 These are Consistent independent
3x+y=4
-6x-2y=-8 These are coincident
Inconsistent lines=No solution
Coincident lines=exactly on top of each other
Consistent Independant= Solution, as they cross each other.
~Hope this helps!
In both cases you may well benefit from graphing the functions.
Do you recognize f(x) = (x + 1)^2 - 1 as a quadratic function, whose graph is that of a parabola that opens up? By comparing this to y = a(x-h)^2 + k, we see that a=1, h= -1 and k = -1. The vertex is at (h,k), which here is the point (-1, -1). This is the minimum value of the function. Thus, the range of this function is [-1, infinity).
Now for the function f(x) = 7x - 11: This is a linear function whose graph is (surprise!) a straight line. When x increases, y increases, without limits to either. Similarly, when x decreases, y decreases.
Thus the range includes all real numbers: (-infinity, infinity).
Answer:
The answer to your questions is: 25 new teachers
Step-by-step explanation:
Data
# of students = 2000
ratio = 3:80 teachers to students
New teachers = ?
Process
I suggest to use rule of three to solve this problem
3 teachers ---------------- 80 students
x ---------------- 2000 students
x = (2000 x 3) / 80 = 75 teachers
Number of initial teachers = 75
The ratio change to 1:20
1 teacher ------------------- 20 students
x ------------------- 2000 students
x = (2000 x 1) / 20
x = 100 teachers
Number of new teachers = 100 - 75 = 25
