Math Problem Statement

Identify the x and y intercepts of each equation: a) 10x + 4y = 20; b) 4x - 8y = -40; c) x = -5; d) y = 3

Solution

Let's solve the given equations to find their x-intercepts and y-intercepts.

a) 10x+4y=2010x + 4y = 20

  • x-intercept: Set y=0y = 0 and solve for xx. 10x+4(0)=20    10x=20    x=210x + 4(0) = 20 \implies 10x = 20 \implies x = 2 The x-intercept is (2,0)(2, 0).

  • y-intercept: Set x=0x = 0 and solve for yy. 10(0)+4y=20    4y=20    y=510(0) + 4y = 20 \implies 4y = 20 \implies y = 5 The y-intercept is (0,5)(0, 5).

b) 4x8y=404x - 8y = -40

  • x-intercept: Set y=0y = 0 and solve for xx. 4x8(0)=40    4x=40    x=104x - 8(0) = -40 \implies 4x = -40 \implies x = -10 The x-intercept is (10,0)(-10, 0).

  • y-intercept: Set x=0x = 0 and solve for yy. 4(0)8y=40    8y=40    y=54(0) - 8y = -40 \implies -8y = -40 \implies y = 5 The y-intercept is (0,5)(0, 5).

c) x=5x = -5

This is a vertical line, so it only has an x-intercept.

  • x-intercept: x=5x = -5, so the intercept is (5,0)(-5, 0).
  • y-intercept: Since it's a vertical line, there is no y-intercept.

d) y=3y = 3

This is a horizontal line, so it only has a y-intercept.

  • x-intercept: A horizontal line has no x-intercept.
  • y-intercept: y=3y = 3, so the intercept is (0,3)(0, 3).

Summary of the intercepts:

a) x-int: 22, y-int: 55
b) x-int: 10-10, y-int: 55
c) x-int: 5-5, y-int: None
d) x-int: None, y-int: 33

Let me know if you need more details or if you have any questions!

Here are some additional related questions to consider:

  1. How do you find intercepts for non-linear equations?
  2. What does the slope of a line tell us about the relationship between x and y?
  3. Can a line have both intercepts equal to zero? What does that mean geometrically?
  4. What is the intercept form of the equation of a line?
  5. How would intercepts change if the coefficients in the equation were fractions?

Tip: Always substitute x=0x = 0 for y-intercepts and y=0y = 0 for x-intercepts to solve these kinds of problems easily.

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Math Problem Analysis

Mathematical Concepts

Linear equations
Intercepts

Formulas

To find the x-intercept: set y = 0 and solve for x
To find the y-intercept: set x = 0 and solve for y

Theorems

The x- and y-intercepts of a linear equation

Suitable Grade Level

Grades 7-10