Solve Quadratic Equation x^2 - 9 for X-Axis Intersections

Question

Determine the points of intersection of the function

y=(x+3)(x3) y=(x+3)(x-3)

With the X

Video Solution

Solution Steps

00:00 Find the intersection point with X-axis
00:03 At the intersection point with X-axis, Y value must = 0
00:07 Substitute Y = 0 and solve for X values
00:14 Find what makes each factor zero in the product
00:20 This is one solution
00:28 This is the second solution
00:35 And this is the solution to the question

Step-by-Step Solution

To determine the points of intersection of the function y=(x+3)(x3) y = (x+3)(x-3) with the x-axis, we need to find the x-values where y=0 y = 0 . These are called the x-intercepts.

We begin by setting the function equal to zero:

(x+3)(x3)=0 (x+3)(x-3) = 0

Using the zero-product property, if a product of two terms is zero, then at least one of the factors must be zero. Thus, we set each factor equal to zero and solve for x x :

  • First factor: x+3=0 x + 3 = 0
    • Solving for x x , we subtract 3 from both sides:
      x=3 x = -3
  • Second factor: x3=0 x - 3 = 0
    • Solving for x x , we add 3 to both sides:
      x=3 x = 3

Hence, the solutions for x x where y=0 y = 0 are x=3 x = -3 and x=3 x = 3 .

Therefore, the points of intersection of the function with the x-axis are (3,0) (-3, 0) and (3,0) (3, 0) .

Comparing with the given answer choices, the correct choice is (3,0),(3,0) (3,0),(-3,0) .

Therefore, the points of intersection are (3,0),(3,0) (3,0),(-3,0) .

Answer

(3,0),(3,0) (3,0),(-3,0)