Question

Find the GCF of 72 and 81. Show your work. (3 points) Part C: Using the GCF you found in Part B, rewrite 72 + 81 as two factors. One factor is the GCF and the other is the sum of two numbers that do not have a common factor. Show your work. (4 points)

Answer 1

Answer: B. GCF of 72 and 81 is 9.

C. 72+81 = 9(8+9)

Step-by-step explanation:

The greatest common factor of two or more numbers is the highest number that divides all of them.

Given numbers : 72 and 81

Prime factorization of 72 and 81:

72 = 2 x 2 x 2 x 3 x 3

81= 3 x 3 x 3 x 3

GCF(72,81) = 3x 3 =9

Consider 72+81 = 9 x 8 + 9 x 9     [72= 8 x 9, 81 = 9 x 9]

= 9(8+9)

Hence, B. GCF of 72 and 81 is 9.

C. 72+81 = 9(8+9)