Question

The equation of line p is y = x − 1 .

Line q is parallel to line p and passes through (–2, 8) .
What is the equation of line q ?
Write the equation in slope-intercept form. Write the numbers in the equation as proper fractions, improper fractions, or integers.

Answer 1

y = x + 10

Explanation:

Slope = 1

y = x + c

When x = -2, y = 8

8 = -2 + c

c = 10

y = x + 10

Answer 2

Explanation:

The equation of a straight line can be represented in the slope intercept form as

y = mx + c

Where

m = slope = (change in the value of y in the y axis) / (change in the value of x in the x axis)

The equation of the given line p is

y = x - 1

Comparing with the slope intercept form, slope = 1

If two lines are parallel, it means that they have the same slope. Therefore, the slope of line q passing through (- 2, 8) is 1

To determine the y intercept, we would substitute m = 1, x = - 2 and

y = 8 into y = mx + c. It becomes

8 = 1 × - 2 + c

8 = - 2 + c

c = 8 + 2 = 10

The equation becomes

y = x + 10