Question
Which of the following are solutions to 2x2 - 8x - 90? Select all that apply.
show your work
A 2
B -5
C -7
D 9
E 15
F 5
G 7
show your work
A 2
B -5
C -7
D 9
E 15
F 5
G 7
Answers
Answered by
GPT 3.5
To find the solutions to the equation 2x^2 - 8x - 90, we can use the quadratic formula:
x = (-b ± √(b^2 - 4ac)) / 2a
Where a = 2, b = -8, and c = -90.
Plugging these values into the formula:
x = (8 ± √((-8)^2 - 4*2*(-90))) / 2*2
x = (8 ± √(64 + 720)) / 4
x = (8 ± √784) / 4
x = (8 ± 28) / 4
So, the solutions are x = (8 + 28) / 4 = 36/4 = 9, and x = (8 - 28) / 4 = -20/4 = -5.
Therefore, the solutions to the equation 2x^2 - 8x - 90 are B: -5 and D: 9.
x = (-b ± √(b^2 - 4ac)) / 2a
Where a = 2, b = -8, and c = -90.
Plugging these values into the formula:
x = (8 ± √((-8)^2 - 4*2*(-90))) / 2*2
x = (8 ± √(64 + 720)) / 4
x = (8 ± √784) / 4
x = (8 ± 28) / 4
So, the solutions are x = (8 + 28) / 4 = 36/4 = 9, and x = (8 - 28) / 4 = -20/4 = -5.
Therefore, the solutions to the equation 2x^2 - 8x - 90 are B: -5 and D: 9.