Question

Can you think of a few examples of how we write mathematical expressions in real-life?

Answer 1

im having trouble writing how i use them

Answer 2

pretty much say anything you can think of relating two things by some numerical relation and it can be translated into algebra

Answer 3

I am thinking of a number. If I add 2 to that number, I will get 5. What is the number?

Although it may be fairly easy to guess that the number is 3,

Let x be the number in my mind.

Add 2 to x to get 5

Adding 2 to x to get 5 means that whatever x is, when I add 2 to x, it has to equal to 5

The equation is

2 + x = 5

Answer 4

johnny is older than kate
age of johnny=J
age of kate=K
translates to
J>k

Answer 5

Soon or later, all of us use the service of a taxi driver

Taxi drivers usually charge a an initial fixed fee as part of using their services. Then, for each mileage, they charge a certain amount

Say for instance, the initial fee is 4 dollars and each mileage cost 2 dollars

The total cost can be modeled with an equation that is linear.

Let y be the total cost

Let N be number of mileage

Total cost = 4 + cost for N miles

Notice that cost for N miles = N×2

Therefore, y = 4 + N×2

Say for instance, a taxi driver takes you to a distance of 20 miles, how much money do you have to pay using y = 4 + N×2 ?

When N = 20, Y = 4 + 20×2 = 4 + 40 = 44 dollars

Now, let's ask the question the other way around!

If you pay 60 dollars, how far did the taxi driver took you?

This time y = 60

Replacing 60 into the equation gives you the following equation:

60 = 4 + N×2

It is not obvious to see that N = 28.

That is why it is important to learn to solve linear equations!

Answer 6

thank you

Answer 7

welcome :)

Answer 8

welcome :)

Answer 9

I just went for a very simple example
there are also classic problems like...
I have a total of 20 coins
they are all dimes and quarters that total $11.50
how many of each coin do I have?
x=#dimes
y=#quarters
if you have 20 coins then
x+y=20
and if the amount of money totals (money per coin)x(# that coin) then
0.1x+0.25y=11.50

you then have two equations
x+y=20
0.1x+0.25y=11.50

you can use these two eqns to solve for the number of each coin, x an y