By randomly assigning subjects to treatment conditions, many extraneous variables are automatically across conditions.

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?

What is the value of x in the equation 1/5x - 2/3y = 30 , when y = 15

The length of a rectangular plot of land is given by the expression 6x^3y^4. the width of the plot is given by the expression 5x^5y^4z. find an expression to represent the area of the rectangular plot.