Tangents & normal lines challenge

Review your differentiation skills with some challenge problems about finding tangent and normal lines.

Problem

In terms of k, space where k, is greater than, 0, space, what is the y-intercept of the line tangent to the curve f, left parenthesis, x, right parenthesis, equals, square root of, x, end square root, space at the point on the curve where x, equals, k?
Please choose from one of the following options.