I: x-2y>=8
II:2x+y<=3
start by isolating y on a side
with I:
x-2y>=8
-2y>=8-x
2y<=x-8
y<=x/2-4
with II:
2x+y<=3
y<=-2x+3
now you can draw I' and II' and read of the solutions with the graph.
transform the inequalities into lines in slope intercept form by replacing the inequality with equality:
y<=x/2-4
->
y=x/2-4
y<=-2x+3
->
y=-2x+3
look at the inequalities to figure out if the area above or below is valid for each line (y<=... -> area below is valid->colored in the attached image)
the area in which all areas overlap is the solution space.
Answer:
Get a calculator
Step-by-step explanation:
Most of the time for simple math like multiplying 2 digits, it is easiest if you just get a calculator. It saves a lot of time.
If you can't get a calculator then i recommend memorizing some common equations.
For example 10*15= 150
so that if you get 12*15=?, you can easily just add two extra 15's to your answer of 150.
15+15 is 30, and 30+150(from 10*15)=180.
Therefore 12*15=180.
:) Hope that helped!
The first statement "<span>y varies directly as x" means that as y increases, x also increases. To help us we need to assign a proportionality constant, k. We can now say:</span>
y=kx where k is just a constant. Then substitute the values,
180=kn
n=5k
With these equation we know that k is equal to (positive or negative) 6 and therefore we can get n to be (positive or negative) 30.
Slope is defined as the change in y divided by the change in x between two points.
Slope = y2 - y1/x2 - x1
-2 - 4/ -1 - (-4)
-6/3
-2
Hope this helps!