Which of the following are necessary when proving that the opposite sides of a parallelogram are congruent? Check all that apply.
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Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

What are the coordinates of the point is 1/4 of the way from a (-6, -3) to b (6, 1)? a. (-3, -2) b. (0, -2) c. (-1, 0) d. (3, 2)

If chord ab is congruent to chord cd, then what must be true about ef and eg?