Assume x equals expression: Let's assume x equals the entire expression. So, x=7+7+7+….
Substitute x in square root: Since the expression inside the square root is the same as x, we can substitute x inside the square root. So, we get x=7+x.
Square both sides: Now, we square both sides to get rid of the square root. This gives us x2=7+x.
Rearrange to quadratic equation: Rearrange the equation to get a quadratic equation: x2−x−7=0.
Solve using quadratic formula: We can solve this quadratic equation using the quadratic formula, x=2a−b±b2−4ac, where a=1, b=−1, and c=−7.
Plug values in formula: Plugging the values into the quadratic formula gives us x=21±1+4×7.
Simplify square root: Simplify the expression under the square root: x=21±29.
Take positive solution: Since x is the length and cannot be negative, we take the positive solution: x=21+29.