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4 votes
How do I do this lol

How do I do this lol-example-1
User Dhondup
by
6.8k points

2 Answers

3 votes

Answer:

x = 6, x = 7

Explanation:

Given

x =
√(13x-42) ← square both sides

x² = 13x - 42 ← subtract 13x - 42 from both sides

x² - 13x + 42 = 0 ← in standard form

(x - 6)(x - 7) = 0 ← in factored form

Equate each factor to zero and solve for x

x - 6 = 0 ⇒ x = 6

x - 7 = 0 ⇒ x = 7

As a check substitute these values into the right side of the equation and if equal to the left side then they are the solutions

x = 6 :
√(78-42) =
√(36) = 6 ← solution

x = 7 :
√(91-42) =
√(49) = 7 ← solution

User AZorin
by
6.7k points
5 votes

Assignment:
\bold{Solve \ Equation: \ x=√(13x-42)}

<><><><><><><>

Answer:
\boxed{\bold{x=7,\:x=6}}

<><><><><><><>

Explanation:
\downarrow\downarrow\downarrow

<><><><><><><>

[ Step One ] Square Both Sides


\bold{x^2=\left(√(13x-42)\right)^2}

[ Step Two ] Expand
\bold{\left(√(13x-42)\right)^2}


\bold{13x-42}

[ Step Three ] Rewrite Equation


\bold{x^2=13x-42}

[ Step Four ] Solve
\bold{x^2=13x-42}


\bold{x=7,\:x=6}

<><><><><><><>


\bold{\rightarrow Mordancy \leftarrow}

User Ccocker
by
7.5k points