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Finding x and y intercepts of an equation. It's easy to identify the x and y intercepts on a graph, but students frequently struggle to find them using only the equation.

User Greenstick
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2 Answers

12 votes
12 votes

You can easily find x and y intercepts using two easiest ways (There are more but these are easiest)

Let's see

#1

Suppose a equation given

  • ax+by+c=0

Now

  • For x intercept put y=0 and find x value .
  • For y intercept put x=0 and find y value

#2

This way is only possible if you know how to create equation from points or convert one equation form to another form

The intercept form you need to manage

  • x/a+y/b=1

  • Just take c to left side then divide all variables by c and make right side 1

a is x intercept

b is y intercept

User Sharel
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3.0k points
18 votes
18 votes

Answer:

The y-intercept is when x = 0 (where the line crosses the y-axis), so look for the constant in the equation (without a variable).

For example, the y-intercept for the equation y = 2x + 4 is 4.

The y-intercept for the equation y = 3x² - 6x + 8 is 8.

The x-intercept is when y = 0 (where the line crosses the x-axis). This can be trickier to find (without simply setting the equation to zero and solving for x), depending on the type of equation.

If the equation is a polynomial that can be factored, then the x-intercepts are easier to spot, as each of the factors equals zero.

For example, the x-intercepts for the equation y = x(x - 2)(x + 3)(x - 1) are 0, 2, -3 and 1 as (x - 2) = 0 so x = 2 and so on.

For a linear equation in the form y = mx + b the x-intercept would be
-(b)/(m)

User Roman Smoliar
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3.1k points