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Find the solution of this system of equation -7x+y=-20 9x-3y=36

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days

Pyramid shown has a square base that is 18 inches on each side has a surface area of 164 square inches what is the slant height