Solve for x in the following equation.
The equation is already set to zero.
Method 1: Factoring
The equation can be written in the equivalent form of The only way that a product can equal zero is if one or both of the factors equal zero.
Both answers are 8. This means that 8 is a double zero or double solution.
Method 2: Completing the square
Subtract 64 from both sides of the equation.
Add to both sides of the equation.
Factor the left side and simplify the right side.
Take the square root of both sides of the equation,
Add 8 to both sides of the equation.
Method 3: Quadratic Formula
The quadratic formula is
In the equation , a is the coefficient of the term, b is the coefficient of the x term, and c is the constant. Simply insert 1 for a, -16 for b, and 64 for c in the quadratic formula and simplify
Method 4: Graphing
Graph y= the left side of the equation or and graph y= the right side of the equation or y=0. The graph of y=0 is nothing more than the x-axis. So what you will be looking for is where the graph of crosses the x-axis. Another way of saying this is that the x-intercepts are the solutions to this equation.
The only x-intercept is located at x=8. When the graph is tangent to the x-axis at x=8, it means that there is a double zero (or solution or x-intercept) at The answer is
Check these answer in the original equation.
Check the answer x=8 by substituting 8 in the original equation for x. If the left side of the equation equals the right side of the equation after the substitution, you have found the correct answer.
Since the left side of the original equation is equal to the right side of the original equation after we substitute the value 8 for x, then x=8 is a solution.
The solution to the equation is 8.
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