What is the greatest common factor of 21 40

Algebra 1: unit 6 part 2 of test a) the table shows a linear function. x 0 1 2 3 5 13 21 29 37 45 53 (a) determine the difference of outputs of any two inputs that are 1 unit apart. show your work. (b) determine the difference of outputs of any two inputs that are 2 units apart. show your work.

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The base of a triangle exceeds the height by 9 inches. if the area is 180 square inches, find the length of the base and the height of the triangle.