Answer:
The x-intercepts are [tex](2,0)[/tex] and [tex](-4,0)[/tex].
Step-by-step explanation:
We are given the equation
[tex]2(x+1)^2=18[/tex]
Begin by dividing both sides of the equation by 2:
[tex](x+1)^2=9[/tex]
Next, take the square root of both sides. Remember that there are two solutions to a square root, the positive and the negative root:
[tex]x+1=\pm3[/tex]
Split the equation into two based on the two solutions:
[tex]x+1=-3[/tex]
[tex]x+1=3[/tex]
Solve each equation by subtracting 1 from both sides:
[tex]x=-4\\ x=2[/tex]
Since the x-intercepts are the solutions to a quadratic, we know the solutions are (2,0) and (-4,0).