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Question 3 Unsaved Solve for x, given the equation Square root of x minus 5 + 7 = 11

2 Answers

4 votes

We have the following equation:


√(x-5) +7=11

To solve this, we first need to subtract the 7 on both sides of the equation.


√(x-5) +7-7=11-7

The equation then becomes:


√(x-5) =4

Now we must square both sides of the equation to get rid of the radical/square root symbol.


(√(x-5))^2 =(4)^2

Now we have a normal one step equation.


x-5=16

Add 5 on both sides to find x.


x-5+5=16+5

x=21

To see if this solution is true, we must substitute 21 back into the original equation.


√(21-5) +7=11


√(16) +7=11


4+7=11

11=11

Therefore, the solution is true.

User Someth Victory
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5.5k points
3 votes


Domain:\\\\x-5\geq0\to x\geq5\\\\√(x-5)+7=11\ \ \ \ \ |-7\\\\√(x-5)=4\ \ \ \ \ |^2\\\\(√(x-5))^2=4^2\to x-5=16\ \ \ \ \ |+5\\\\\boxed{x=21}\in D\\\\

User Thomas Cook
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5.1k points