I know the answer is 5, -3/4 but I am missing something. please help show each step and use quadratic formula. thank you

{17 + √[(-17)

^{2}-(4)(4)(-15)]}/ (2*4) = 40/8 = 51. square -17 = 289

2. multiply 4, 4, and -15 to get -240

3. subtract -240 from 289 = 289--240= 289+240= 529

4. take the square root of 529 = √529= 23

5. add 23 to 17 = 23+17=40

6. multiply 2 by 4 = 2*4 = 8

7. Divide 40 by 8 = 40/8 =5

3. subtract -240 from 289 = 289--240= 289+240= 529

4. take the square root of 529 = √529= 23

5. add 23 to 17 = 23+17=40

6. multiply 2 by 4 = 2*4 = 8

7. Divide 40 by 8 = 40/8 =5

AND

{17 - √[(-17)

^{2}-(4)(4)(-15)]}/ (2*4) = -6/8 = -3/41. square -17 = 289

2. multiply 4, 4, and -15 to get -240

3. subtract -240 from 289 = 289--240= 289+240= 529

4. take the square root of 529 = √529= 23

5. subtract 23 from 17 = 17-23=-6

6. multiply 2 by 4 = 2*4 = 8

7. Divide -6 by 8 = -6/8 = -3/4

2. multiply 4, 4, and -15 to get -240

3. subtract -240 from 289 = 289--240= 289+240= 529

4. take the square root of 529 = √529= 23

5. subtract 23 from 17 = 17-23=-6

6. multiply 2 by 4 = 2*4 = 8

7. Divide -6 by 8 = -6/8 = -3/4

I hope this helps.