15 : find the equation of the tangent line to the parabola y=x^2 at the point (2, 4). hint: a line y-4=m(x-2) is the tangent to the parabola if and only if the line is non-vertical and the nonlinear system
y=x^2
y=m(x-2)+4
has exactly one solution.

An architect builds a model of a park in the shape of a rectangle. the model is 40.64 centimeters long and 66.04 centimeters wide. one inch equals 2.54 centimeters. use the ratio table to find the ratio of the length to the sum of the length and width in inches and in simplest form. length 40.64 width 66.04 a. 8: 21 b. 13: 21 c. 21: 13 d. 21: 8