Question

write the equation of the line that is parallel to the -3x - 6y= 12 and passing the point (1,-8) in standard form ​

Answer 1

x + 2y = -15

Explanation:

simplify -3x - 6y = 12 by dividing a -3 from each term to get:

x + 2y = -4

now put into slope-intercept form to get:

2y = -x - 4

y = -1x/2 - 2

parallel lines have the same slope so we know our answer must have a slope of -1/2

now we can plug (1,-8) into y=mx + b to get the 'y-intercept', or 'b'

-8 = 1(-1/2) + b

-8 = -1/2 + b

b = -7 1/2 or -15/2

we now know the slope and the y-intercept so our answer is:

y = -x/2 - 15/2

re-write in standard form, which is ax + by = c

multiply each term by 2 to get:

2y = -x - 15

add 'x' to each side to get:

2y + x = -15

x + 2y = -15