How do you write a slope-intercept equation for a line parallel to the line x-2y=6 which passes through the point (-5,2)?

2 Answers
Dec 19, 2017

y = 1/2 x + 9/2

Explanation:

We know,
If there are two equations of line like
a_1x + b_1y + c_1 = 0 and a_2x + b_2x + c_2 = 0 ;

then, the condition of they being parallel is

a_1/a_2 = b_1/b_2 != c_1/c_2

First Convert the line equation to the general form ax + by + c = 0

Therefore, x - 2y = 6

rArr x - 2y - 6 = 0 ..........................(i)

Then, the equation of parallel line will be

x - 2y + k = 0 ........................................(ii) (k can be any constant)

If it passes through the point (-5, 2), then the equation will be satisfied with these values.

Lets put x = -5 and y = 2 in eq(ii).

Therefore, x - 2y + k = 0
rArr (-5) - 2(2) +k = 0
rArr -5 - 4 + k = 0
rArr k = 9

Then the required equation will be x - 2y + 9 = 0.

The equation, at slope-intercept form is

x - 2y + 9 = 0
rArr -2y = -x - 9
rArr 2y = x + 9
rArr y = 1/2 x + 9/2, where the slope is m = 1/2 and the y-intercept is c = 9/2.

graph{y = (x + 9)/2 [-20.27, 20.26, -10.14, 10.13]}

Dec 19, 2017

y=1/2x+9/2

Explanation:

• " parallel lines have equal slopes"

"the equation of a line in "color(blue)"slope-intercept form" is.

•color(white)(x)y=mx+b

"where m is the slope and b the y-intercept"

"rearrange "x-2y=6" into this form"

rArry=1/2x-3larr" with "m=1/2

rArry=1/2x+blarrcolor(blue)"is the partial equation"

"to find b substitute "(-5,2)" into the partial equation"

2=-5/2+brArrb=9/2

rArry=1/2x+9/2larrcolor(red)"in slope-intercept form"