Dimitri is solving the following equation for x.2x2−7=33His first few steps are given below.2x2=40x2=20x=±20Is it necessary for Dimitri to check his answers for extraneous solutions?Choose 1 answer:(A) Yes(B) No
Q. Dimitri is solving the following equation for x.2x2−7=33His first few steps are given below.2x2=40x2=20x=±20Is it necessary for Dimitri to check his answers for extraneous solutions?Choose 1 answer:(A) Yes(B) No
Isolate x2 term: Dimitri is solving the equation 2x2−7=33 for x. The first step is to isolate the x2 term by adding 7 to both sides of the equation.Calculation: 2x2−7+7=33+72x2=40
Divide by 2: Next, Dimitri divides both sides of the equation by 2 to solve for x2.Calculation: 22x2=240x2=20
Take square root: Dimitri then takes the square root of both sides to solve for x. Since the square root has both a positive and negative solution, he writes x as plus or minus the square root of 20.Calculation: x=±20
Simplify square root: Dimitri simplifies 20 to (4⋅5) to make it easier to take the square root.Calculation: x=±(4⋅5)=±25
Check for extraneous solutions: Now, we need to answer the "Is it necessary for Dimitri to check his answers for extraneous solutions?" Since Dimitri has performed operations that are valid for all real numbers (adding, subtracting, multiplying, dividing by a non-zero number, and taking even roots of positive numbers), there is no need to check for extraneous solutions. The operations he used do not introduce any solutions that weren't already present in the original equation.
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