Math Problem Statement

What is an equation of the line that passes through the point left parenthesis, minus, 1, comma, minus, 4, right parenthesis(−1,−4) and is parallel to the line x, plus, y, equals, 7x+y=7?

Solution

The equation of a line that is parallel to another line will have the same slope.

First, let's rewrite the equation of the given line x+y=7x + y = 7 in slope-intercept form, y=mx+by = mx + b, where mm is the slope:

x+y=7(subtract x from both sides)x + y = 7 \quad \text{(subtract } x \text{ from both sides)} y=x+7y = -x + 7

From this equation, we can see that the slope mm of the line is 1-1.

Now, since we want the equation of a line parallel to this one, the slope of our new line will also be m=1m = -1.

Next, we use the point-slope form of a line, which is given by:

yy1=m(xx1)y - y_1 = m(x - x_1)

Here, (x1,y1)=(1,4)(x_1, y_1) = (-1, -4) is the point through which the line passes, and m=1m = -1. Plugging these values into the equation:

y(4)=1(x(1))y - (-4) = -1(x - (-1)) y+4=1(x+1)y + 4 = -1(x + 1) y+4=x1y + 4 = -x - 1 y=x14y = -x - 1 - 4 y=x5y = -x - 5

Thus, the equation of the line is:

y=x5y = -x - 5

Would you like further details or have any questions?

Here are five related questions you can explore:

  1. How do you convert a line from standard form to slope-intercept form?
  2. What is the point-slope form of a line, and when is it useful?
  3. How do you find the slope of a line given two points?
  4. What does it mean for two lines to be parallel?
  5. How can you find the equation of a line perpendicular to a given line?

Tip: The slope-intercept form, y=mx+by = mx + b, is often the easiest way to graph a line since it directly gives the slope and the y-intercept.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Linear Equations
Parallel Lines
Slope-Intercept Form
Point-Slope Form

Formulas

Slope-Intercept Form: y = mx + b
Point-Slope Form: y - y1 = m(x - x1)

Theorems

Lines with the same slope are parallel

Suitable Grade Level

Grades 8-10