Question

Write an equation of a line in slope intercept form that is PARALLEL to the line x−3y=15 and contains the point (0,7).

Answer 1

eqn of line : x-3y=15

slope1=m= -coefficient of x/coefficient of y=1/3

As lines are parallel slope must be equal.

slope3=m'=1/3

passing points of second line =(0,7)

eqn of line = (y-y')=m(x-x')

=(y-7)=1/3(x-0)

=y-7=1/3x

=1/3x-y+7=0

=x-3y+21=0

Answer 2

Answer:

First of all,

the slope intercept form is , y - y¹ = m(x - x¹). (I)

if the required line is parallel to given line then their slopes are equal,

x - 3y = 15

x - 15 = 3y

y = x/3 - 5. (ii)

y = mx + c. (iii)

then the slope m = 1/3

now,

put the value of point (0,7) in equation (I) at the place of y¹ and x¹

y - 7 = 1/3 (x - 0)

y - 7 = x/3

3y - 21 = x

x - 3y + 21 =0 , is the equation for the required line have points (0,7)