Question

50 POINTS

Does the point (1, 3) fall on the graph of the line that goes through (-2, 8) and (3, -1)? Show me how you know without graphing. Show your work algebraically (That is, don't draw me a graph... show me using numbers, variables, and/or symbols).



can someone explain please :)​

Answer 1

Explanation:

1.First work out the equation of the line.

1.1 work out gradient

`y = ( ( - 1 - 8)/(3 - ( - 2)) )x + c`

`y = - (9)/(5) x + c`

1.2 substitute in x and y value of one of the two given point. ill use (3;-1).

`- 1 = - (9)/(5) (3) + c`

`c = (22)/(5)`

therefore equation is

`y = - (9)/(5) x + (22)/(5)`

2. Now sub in x value of the point you want to test and see if y value correlates.

`y = - (9)/(5) (1) + (22)/(5)`

`y = (13)/(5)`

3. We can conclude that point (3;1) does not fall on the graph