Joyce is trying to solve the equation y = x2 - 8x + 7 using the quadratic formula. She has made an error in one of the steps below. Find the step where Joyce went wrong. Step 1: x equals negative 8 plus or minus the square root of the quantity eight squared minus four times one times seven, end q Step 2: x equals negative 8 plus or minus the square root of sixty-four minus twenty-eight all over two times one. Step 3: x equals negative 8 plus or minus the square root of thirty-six all over two times one. Step 4: x equals negative 8 plus or minus six all over two.

Question

Greyson Phillips

Mathematics

17 December, 06:51

Joyce is trying to solve the equation y = x2 - 8x + 7 using the quadratic formula. She has made an error in one of the steps below. Find the step where Joyce went wrong. Step 1: x equals negative 8 plus or minus the square root of the quantity eight squared minus four times one times seven, end q Step 2: x equals negative 8 plus or minus the square root of sixty-four minus twenty-eight all over two times one. Step 3: x equals negative 8 plus or minus the square root of thirty-six all over two times one. Step 4: x equals negative 8 plus or minus six all over two.

+3

Answers (2)

Know the Answer?

Reyna Zuniga · Answer 1

Step 1

Step-by-step explanation

Just finished the test and got it correct

Pinto · Answer 2

The error is in the first step. It should be (+8 plus or minus the square root of the quantity eight squared minus four times one times seven). This is because "b" is - 8 so - b is - (-8) = + 8