Math Problem Statement

The equation of line s is y = -1/9 x - 4. Line t includes the point (1, 7) and is perpendicular to line s. What is the equation of line t?

Solution

Let's break this down to find the equation of line tt.

Step 1: Identify the slope of line ss

The equation of line ss is given as:

y=19x4y = -\frac{1}{9}x - 4

From this equation, the slope of line ss is ms=19m_s = -\frac{1}{9}.

Step 2: Find the slope of line tt

Since line tt is perpendicular to line ss, the slopes of perpendicular lines are negative reciprocals of each other. The negative reciprocal of 19-\frac{1}{9} is:

mt=9m_t = 9

So, the slope of line tt is 99.

Step 3: Use the point-slope form

Line tt passes through the point (1,7)(1, 7). We will use the point-slope form of the equation of a line:

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

where (x1,y1)(x_1, y_1) is the point (1,7)(1, 7), and mm is the slope 99.

Substituting the values:

y7=9(x1)y - 7 = 9(x - 1)

Step 4: Simplify to slope-intercept form

Now, expand and simplify the equation:

y7=9x9y - 7 = 9x - 9

y=9x9+7y = 9x - 9 + 7

y=9x2y = 9x - 2

Final Answer:

The equation of line tt is:

y=9x2y = 9x - 2

Would you like any further details or clarification on this?

Here are five related questions:

  1. How do you find the slope of a line given its equation in standard form?
  2. What is the relationship between the slopes of perpendicular lines?
  3. How do you convert between different forms of linear equations (slope-intercept, point-slope, standard)?
  4. Can two lines with the same slope ever be perpendicular? Why or why not?
  5. How do you graph a line given its slope and a point on the line?

Tip: Always check that the slope of the new line is the negative reciprocal when dealing with perpendicular lines.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Linear Equations
Slope-Intercept Form
Perpendicular Lines

Formulas

Slope-intercept form: y = mx + b
Point-slope form: y - y1 = m(x - x1)
Relationship of slopes for perpendicular lines: m1 * m2 = -1

Theorems

If two lines are perpendicular, the product of their slopes is -1.

Suitable Grade Level

Grades 8-10