Congruent Triangles on the Coordinate Plane, HELP

Which is the most efficient first step to solve x in the equation 3.7x - 18 = -4.3x -34 a. add 3.7x to both sides of the equation. b. add 4.3x to both sides of the equation. c. subtract 18 from both sides of the equation. d. subtract 34 from both sides of the equation.

What is the slope of the line that contains the points (-2,1) and (0,-3)

2.5 milligrams is equivalent to how many grams