Question

Line CD passes through (0, 1) and is parallel to x + y = 3. Write the standard form of the equation of line CD.

a. x + y = 1
b. x – y = 1
c. x + 1 = y
d. x + y = 11

Answer 1

A. would be the correct choice because the x+y hast to =1.

Answer 2

Answer: a.
`x+y=1`

Explanation:

Given: Line CD passes through (0, 1) and is parallel to
`x+y=3`.

We know that if two line are parallel then they have equal slopes.

Thus, the slope of line = slope of line
`x+y=3`.

`x+y=3\\\Rightarrowy=3-x` when we compare this to the standard linear equation
`y=mx+c`.we get
`m=-1`.

Hence, slope of CD (m)= -1

Now, the equation of line CD passing through (0,1) is given by :-

`(y-1)=m(x-0)\\\Rightarrow(y-1)=(-1)x\\\Rightarrow x+y=1`

Thus, the equation of line CD =
`x+y=1`