# Help with math question?

It's 2,6 and -6,-8,. I have to find x and y. I got 7/4 but it's marked as wrong can you tell me what I did wrong?

You said you have to find x and y

what does that mean?

x = 2 and -6 in the two points you mentioned

y = 6 and -8 in the two points you mentioned

m = 7/4 is just the slope or the rate of change of y / rate of change of x

if this is a line, it represents an infinite number of x and y pairs

so you need to write down an infinite number of pairs to find all x and y values

you can an find equation , y = mx +b

you can find the y-intercept = b (set x = 0 and solve for y )

y = b

you can find the x -intercept (set y = 0 and solve for x )

0 = mx +b

mx =-b

x-intercept = -b /m

you want an equation of a line

y = mx +b

(7/4) is just m , it does not include b

(2,6) (-6, -8)

m = (-8 - (-6) ) / (-6 - 2) = -14/ -8 = 7/4

y = (7/4)x +b

(2,6)

6 =(7/4)*2 + b

b = 6 - (7/4)*2 = 6 - (7/4)*2 = (12 -7)/2 = 5/2

b = 5/2

=== equation of the line

y = (7/4)x + 5/2

=== x-intercept

x-intercept : 5/2

==== y-intercept

y-intercept: (-5/2/ (7/4) = -5/2 *(4/7) = -20/14 = -10/7

=== other points

plug values in the equation

y = (7/4)x + 5/2

x: -6 y: -8

x :0 y : 5/2

x :1 y: 17/4

x : 2 y : 6

x: 3 y : 31/4

x: 4 y : 38/4 = 19/2

and so on

You could find an infinite number of (x, y) pairs

=== equation for y

y = (7/4)x +5/2

solving for x

(7/4)x = y - 5/2

x = (4/7)y - (5/2)*(4/7) = (4/7)y - 10/7

==== equation for x

x = (4/7)y - 10/7

slope= (-8-6)/(-6-2)= -14/-8= 7/4

Here we have the line through (2,6) and (-6,-8) being given by (2--6)(y--8) = (6--8)(x--6) which can be manipulated and simplified to 7x - 4y = -10 in Standard Form, or to y = (7/4)x + 5/2 in Slope Intercept Form, or to x/(-10/7) + y/(5/2) = 1 in (Two) Intercept Form. Hence the x intercept is -10/7 and the y intercept is 5/2.

Graphs: https://www.desmos.com/calculator/03cpw5...

Question , as given , has no meaning.

Out of interest we have two points (2,6) and (-6,8)

gradient , m = 2 (-8) = - 1/4

Equation of line that passes thro` these points is :-

y - 6 = (-1/4) (x - 2)

y = (-1/4) x + 13/2