Q. Solve the equation for all values of x.∣2x+9∣=xAnswer: x=
Consider Non-Negative Case: We have the equation ∣2x+9∣=x. To solve this, we need to consider two cases because the absolute value function outputs the distance from zero, which is always non-negative. The two cases are when the expression inside the absolute value is non-negative and when it is negative.
Solve for x: First, let's consider the case when the expression inside the absolute value is non-negative, which means 2x+9≥0. In this case, the absolute value function does not change the sign of the expression inside it.So we have 2x+9=x.Now, let's solve for x.Subtract x from both sides to get x+9=0.Subtract 9 from both sides to get x=−9.
Check Validity of Solution: We need to check if our solution from Step 2 satisfies the original condition 2x+9≥0. Substitute x with −9 and check: 2(−9)+9=−18+9=−9, which is not greater than or equal to 0. Therefore, x=−9 does not satisfy the condition 2x+9≥0, so it is not a valid solution.
Consider Negative Case: Now, let's consider the second case when the expression inside the absolute value is negative, which means 2x + 9 < 0. In this case, the absolute value function changes the sign of the expression inside it.So we have −(2x+9)=x.Now, let's solve for x.Distribute the negative sign to get −2x−9=x.Add 2x to both sides to get −9=3x.Divide both sides by 3 to get x=−3.
Solve for x: We need to check if our solution from Step 4 satisfies the original condition 2x + 9 < 0. Substitute x with −3 and check: 2(−3)+9=−6+9=3, which is not less than 0. Therefore, x=−3 does not satisfy the condition 2x + 9 < 0, so it is not a valid solution.
Check Validity of Solution: Since neither of the solutions from Step 2 and Step 4 satisfy their respective conditions, we conclude that there are no solutions to the equation ∣2x+9∣=x.
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