Which of these could be a step to prove that BC^2 = AB^2 + AC^2? Options:
1. By distrubtion, AC^2 plus AB^2 = BC multiplied by the quantity DC plus AB.

2. By distrubtion, AC^2 plus AB^2 = BC multiplied by the quantity DC plus BD.

3. By distrubtion, AC^2 plus AD^2 = BC multiplied by the quantity DC plus AB.

4. By distrubtion, AC^2 plus AD^2 = BC multiplied by the quantity DC plus BD.

You are cycling around europe with friends. a cycling festival is starting soon in barcelona. it will take 4.5 hours to cycle there. how many minutes in total is this?

Girardo is using the model below to solve the equation . girardo uses the following steps: step 1 add 4 negative x-tiles to both sides step 2 add 1 negative unit tile to both sides step 3 the solution is which step could be adjusted so that gerardo's final step results in a positive x-value? in step 1, he should have added 4 positive x-tiles to both sides. in step 1, he should have added 3 negative x-tiles to both sides. in step 2, he should have added 4 negative unit tiles to both sides. in step 2, he should have added 1 positive unit tile to both sides.

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. x^2 - 4x - 5 = 0