Question

Write and equation for each of the lines pictured in the graph below

Answer 1

Explanation:

y=kx+b

1)

(-8,0) (0,2)

`\displaystyle\\\boxed {k=(y_2-y_1)/(x_2-x_1) }\\\\k=(2-0)/(0-(-8)) \\\\k=(2)/(8) \\\\k=0.25\\\\(0,2)\ \ \ \ \\x=0\ \ y=2\\Hence,\\2=0,25*0+b\\2=0+b\\2=b\\Thus,\ \ \ \ y=0.25+2`

2)

(-3,0) (0,-3)

`\displaystyle\\k=(-3-0)/(0-(-3)) \\\\k=(-3)/(3) \\\\k=-1\\\\(0,-3)\\x=0\ \ \ \ y=-3\\Hence,\\-3=-1*0+b\\-3=0+b\\-3=b\\Thus,\ \ \ y=-3x-1`

3)

(0,-9) (3,0)

`\displaystyle\\k=(0-(-9))/(3-0)\\\\ k=(9)/(3) \\\\k=3\\\\(0,-9)\\x=0\ \ \ \ \ y=-9\\Hence,\\-9=3*0+b\\-9=0+b\\-9=b\\Thus,\ \ \ y=3x-9`