Question

find the equation of a straight line joining the points (6,9) and (4,7). Please help im bad at mathematic :( and please do a calculation too.

Answer 1

`\boxed{y=x+3}`

Explanation:

Solve for slope first.

The slope can be found through 2 points.

`slope=(change \: in \: y)/(change \: in \: x)`

`slope=(7-9)/(4-6)`

`slope=(-2)/(-2)`

`slope=1`

Using slope-intercept form.

`y=mx+b\\m=slope\\b=y \: intercept`

`y=1x+b`

Let x = 6 and y = 9.

`9=1(6)+b`

`9-6=b`

`3=b`

`y=1x+3`

Answer 2

y = x+3

Explanation:

First step is to find the slope

m = ( y2-y1)/(x2-x1)

= ( 7-9)/(4 - 6)

= -2 / -2

= 1

The we can put is in slope intercept form

y = mx+b where m is the slope and b is the y intercept

y = 1x+b

Putting in one of the points

9 = 1*6+b

Subtracting 6

9-6 = b

3=b

y = 1x+3

y = x+3