To find the positive zero of the function f(x) = x^2 - 5x - 7, we set the function equal to zero and solve for x:
x^2 - 5x - 7 = 0
Using the quadratic formula: x = (-(-5) ± √((-5)^2 - 4(1)(-7))) / 2(1)
x = (5 ± √(25 + 28)) / 2
x = (5 ± √53) /2
Since we are looking for the positive zero, we will use the positive square root:
x = (5 + √53) / 2
x ≈ (5 + 7.28) / 2
x ≈ 12.28 / 2
x ≈ 6.14
Therefore, the positive zero of the function is approximately x = 6.14, which corresponds to answer choice C.
Find the positive zero of the function f(x)=x^2−5x−7. Round your answer to two decimal places.
A. 5.58
B. 10.66
C. 6.14
D. 3.37
1 answer