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