Answer:
In finding the sum of 2+5 you would go right on the number line, while in finding the sum of -2+(-5) you would go left on the number line
Step-by-step explanation:
Intersection of the first two lines:

Multiply the first equation by 4 and the second by 5:

Subtract the two equations:

Plug this value for y in one of the equation, for example the first:

So, the first point of intersection is 
We can find the intersection of the other two lines in the same way: we start with

Use the fact that x and y are the same to rewrite the second equation as

And since x and y are the same, the second point is 
So, we're looking for a line passing through
and
. We may use the formula to find the equation of a line knowing two of its points, but in this case it is very clear that both points have the same coordinates, so the line must be 
In the attached figure, line
is light green, line
is dark green, and their intersection is point A.
Simiarly, line
is red, line
is orange, and their intersection is B.
As you can see, the line connecting A and B is the red line itself.
We write an inequality:



This equation cannot be solved using trivial methods found in high-school classes, so we resort to graphical examination.

is a linear function while

is an exponential one (with limit zero as

approaches

). We see that

at approximately

and

.
Indeed, using a computer algebra system such as the ones on modern TI calculators and on many internet sites gives equality at

. By observing our graph, we see that

when

or

.
The price of fan was 20 Dollars 55 cents last week.
Step-by-step explanation:
Let,
The price last week = x
As the price is 27% lower than last week, therefore
(100%-27%) * Price last week = $15
73% * x = 15
Solving the percentage;

The price of fan was 20 Dollars 55 cents last week.
Keywords: Percentage, multiplication.
Learn more about percentages at:
#LearnwithBrainly
Answer:
A
Step-by-step explanation: