(6 – 15) divided by (7 – 10) which equals 3

y = 3x + b

Now plug in one of the two points given for x and y. I’ll use the first one listed (7,6).

6 = 3(7) + b

6 = 21 + b

b = -15

The equation is y = 3x – 15

Plug in the numbers 15 – 6/10 – 7 = 9/3 = 3 which is the slope.

Now the formula is y = mx + b where m is the slope and b is the y-intercept.

y = 3x + b

Now take one of the coordinates and plug the x and y value in the equation to get the b.

15 = 3(10) + b

15 = 30 + b

-15 = b

Now put it all together………y = 3x – 15

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

= (6-15)/(7-10)

= -9/-3

= +3

you did the right thing to get the intercept, you just have the wrong slope:

y=mx+b

6=3(7)+b

6=21+b

6-21=b

-15=b

check it:

y=mx+b

y=3x-15

15=3(10)-15

15=30-15

15=15 !

btw,

(-7/3)7 = (-49/3)

y – y1 = m(x – x1)

y – 6 = 3(x – 7)

y – 6 = 3x – 21

y = 3x -15

3/9=1/3

then plug-in points

10=(1/3)15+b

10=5+b

5=b

so you finally get: y=(1/3)x+5

hope I helped you out some & hope you’re feeling better!