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34 votes
34 votes
Solve for x for this problem

Solve for x for this problem-example-1
User Nate Pope
by
3.1k points

2 Answers

27 votes
27 votes

Answer:

x = 5 and 6

Explanation:

1. Square both sides
x - 5 = (x - 5)(x - 5)
2. Simplify the right side
x - 5 = x^2 - 10x + 25
3. Add 5 to both sides
x = x^2 - 10x + 30
4. Subtract x from both sides
0 = x^2 - 11x + 30
5. Factor
0 = (x-5)(x-6)
x = 5,6

User Adrien Givry
by
3.4k points
20 votes
20 votes

Answer:

x = 5 , x = 6

Explanation:


√(x-5) = x - 5 ( square both sides )

x - 5 = (x - 5)² ← expand using FOIL

x - 5 = x² - 10x + 25 ← subtract x - 5 from both sides

0 = x² - 11x + 30 ← in standard form

0 = (x - 5)(x - 6) ← in factored form

equate each factor to zero and solve for x

x - 5 = 0 ⇒ x = 5

x - 6 = 0 ⇒ x = 6

As a check

substitute these values into the equation and if both sides are equal then these values are the solutions.

x = 5

left side =
√(5-5) =
√(0) = 0

right side = 5 - 5 = 0

then x = 5 is a solution

----------------------------------

x = 6

left side =
√(6-5) =
√(1) = 1

right side = 6 - 5 = 1

then x = 6 is a solution

User Mangrio
by
3.3k points