WEBVTT
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Find the value of 𝑥.
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Here, we have a triangle, an equilateral triangle, because all three sides are equal.
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And we know this because of these markings.
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So if all sides are equal, we could take any two sides and set them equal to each other and solve for 𝑥.
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Let’s take these two.
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We can set them equal to each other because we know that they are equal in length.
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So to solve for 𝑥, let’s go ahead and subtract five 𝑥 from both sides of the equation.
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The five 𝑥s cancel and seven 𝑥 minus five 𝑥 is two 𝑥.
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Now, let’s add two to both sides of the equation.
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So we have six equals two 𝑥.
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So now, let’s divide by two.
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And we get that 𝑥 is equal to three.
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Now, we could be done, but just to be safe, let’s pick another set to put together and set equal to each other.
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So to solve, let’s subtract seven 𝑥 from both sides.
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The seven 𝑥s cancel.
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And now, let’s add five to both sides.
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And once again, we get that 𝑥 is equal to three.
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So once again, our final answer is 𝑥 equals three.
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If we wanted to, we could triple check and set five 𝑥 plus four equal to eight 𝑥 minus five.
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However, probably double checking would be just enough.
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So once again, 𝑥 equals three.