Solve each equation in Exercises 15–34 by the square root propert...

Question

Solve each equation in Exercises 15–34 by the square root property.

3x^2 - 1 = 47

Accepted Answer

Hello everyone in this video we're going to be looking at this practice problem where we want to solve five X squared minus four is equal to 3121. And we're trying to solve for X. Which means that we want to try to isolate X on one side of the equation. So I'm gonna start isolating X by adding four to both sides. So that leaves me with five X squared is equal to 3125. Now I'm going to divide by five. So in love with X squared is equal to 625. And from here you can see that I have my ex is isolated to one side but I still have X squared. So in order to get rid of the squared, I'm going to take the square root of both sides. And that leasing with X is equal to the square root of 625. So in this case the square root of Is 25 because 25 times 25 is equal to 625. However, The square root is also negative 25 because if I do negative times negative 25 I still get positive 625. So X is equal to positive or -25. And if I write those solutions out I have X is equal to or -25. So this becomes my final answer for X. And you can see that that aligns with answer choice B. So hopefully this video helped and see you next time.

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