2021 AMC 10 B Fall

Complete problem set with solutions and individual problem pages

Problem 2 Easy

(2021 AMC Fall 10B, Question #2)

  • A.

    4

  • B.

    6

  • C.

    8

  • D.

    10

  • E.

    12

Answer:B

Solution 1:

The line of symmetry divides the shaded figure into two congruent triangles, each with base 3 and height 2 . Therefore, the area of the shaded figure is 2 \cdot\left(\frac{1}{2} \cdot 3 \cdot 2\right)=2 \cdot 3=(\text{B}) 6

Solution 2:

To find the area of the shaded figure, we subtract the area of the smaller triangle (base 4 and height 2 ) from the area of the larger triangle (base 4 and height 5 ): \frac{1}{2} \cdot 4 \cdot 5-\frac{1}{2} \cdot 4 \cdot 2=10-4=(\text{B}) 6

Related Problems
Problem 1 2021 AMC 10 B Fall
Problem 3 2021 AMC 10 B Fall
Problem 4 2021 AMC 10 B Fall
Problem 5 2021 AMC 10 B Fall
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