Completing the Square
2. Solve the equation by completing the square. Show your work.
x^2 – 30x = –125
Step 1: Add to both sides of the equation. (2 points)
Add 225 both sides of the equation
x^2 – 30x + 225 = –125
+ 225
x^2 - 30x + 225 = 100
Step 2: Factor the left side of the equation. Show your work. (2 points)
Hint: It is a perfect square trinomial.
x^2 - 30x + 225 = 100
Factor the left side of the equation:
(x - 15)^2 = 100
Step 3: Take the square root of both sides of the equation from Step 2. (1 point)
√(x - 15)^2 = √100
Step 4: Simplify the radical and solve for x. Show your work. (1 point)
x - 15 = + - 10
x - 15 = 10
x = 25
x - 15 = -10
x = 5
Solutions x = 25, 5
The answer is (A) 15.
(6x -10) makes 80 and (6x+10) makes 100
together that equales 180 degrees. since it is a straight line the sum of the the two would have to equal 180. hope this helped :D
At the start of 2nd day, he completed 4 chairs....at the end of the day, (9 hrs later) he completed 7 chairs....that means he had completed (7-4) = 3 chairs in 9 hrs. 9/3 = 3...that means it takes 3 hrs to complete 1 chair.
He has 7....so he needs 3 more chairs...and if 1 chair takes 3 hrs, then 3 chairs takes (3 * 3) = 9 hrs <===
