Pam solved a quadratic equation. Her work is shown below.In which step did Pam make an error?(x+2)2=16,x+2=±4Step 1x=−2±4Step 2Choose 1 answer:(A) Step 1(B) Step 2
Q. Pam solved a quadratic equation. Her work is shown below.In which step did Pam make an error?(x+2)2=16,x+2=±4Step 1x=−2±4Step 2Choose 1 answer:(A) Step 1(B) Step 2
Equation given: Pam starts with the equation (x+2)2=16.To find the value of x, she needs to take the square root of both sides of the equation.The square root of (x+2)2 is x+2, and the square root of 16 is ±4.This means that x+2 could be either 4 or −4.The correct next step should be x+2=4 or x0.
Taking the square root: Pam's Step 1 shows x+2=4.This is correct for one of the possible solutions, but she has forgotten to consider the second solution x+2=−4.However, since she is only showing one step at a time, this is not necessarily an error yet.
Possible values of x: Pam's Step 2 shows x = 2.This is the correct solution for x + 2 = 4.However, she has not shown the solution for x + 2 = −4, which would give x = −6.The error is that she has not considered both possible solutions to the equation.
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