mappings to graphs coordinates

[confused mum]

Help please!

Simple KS3 stuff I'm sure, but I haven't got a clue.

My sons homework is to map coordinates as follows y = 3x + 4. I do not understand. The first 2 are plotted as 0 4, 1 7, he has then to find the answers to 2 ? , 3 ?, 4 ?, 5 ?.
The second question is y = 3x -1 with the first plotted as 1 2.

Explanations greatly appreciated.

Thanks

 

[Deleted member 4993]

Help please!

Simple KS3 stuff I'm sure, but I haven't got a clue.

My sons homework is to map coordinates as follows y = 3x + 4. I do not understand. The first 2 are plotted as 0 4, 1 7, he has then to find the answers to 2 ? , 3 ?, 4 ?, 5 ?.
The second question is y = 3x -1 with the first plotted as 1 2.

Explanations greatly appreciated.

Thanks

This means that he needs to find the value of the given function at those points.

For example:

The first problem is

y = 3x + 4

at x = 0 - what is the value of 'y'? Let's find out

y = 3*0 + 4 = 4

then first set of point - as (x,y) is (0, 4).

Then

at x = 1 - what is the value of 'y'? Let's find out

y = 3*1 + 4 = 7

then second set of point - as (x,y) is (1, 7).

Then

at x = 2 - what is the value of 'y'? Let's find out

y = 3*2 + 4 = 10

then third set of point - as (x,y) is (2, 10).

and so on....