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1. Solve 2(x + 1)^2 = 18. What are the x-intercepts?

User Yttrium
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1 Answer

12 votes

Answer:

The x-intercepts are
(2,0) and
(-4,0).

Explanation:

We are given the equation


2(x+1)^2=18

Begin by dividing both sides of the equation by 2:


(x+1)^2=9

Next, take the square root of both sides. Remember that there are two solutions to a square root, the positive and the negative root:


x+1=\pm3

Split the equation into two based on the two solutions:


x+1=-3


x+1=3

Solve each equation by subtracting 1 from both sides:


x=-4\\ x=2

Since the x-intercepts are the solutions to a quadratic, we know the solutions are (2,0) and (-4,0).

User Reginaldo Costa
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