Practice Test GeeksAMC12 - American Mathematics Competition 12 Practice Test
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Geometry Flashcards

6 cards from real AMC12 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 6 Geometry flashcards as text

  1. A circle has area 16pi. What is its circumference?

    Answer: 8pi

    From pi*r^2=16pi we get r=4, so C=2pi(4)=8pi.

  2. In right triangle ABC with right angle at B, AB=5 and BC=12. What is sin(A)?

    Answer: 12/13

    The hypotenuse AC=13, and sin(A)=BC/AC=12/13.

  3. The diagonals of a rhombus are 6 and 8. What is its side length?

    Answer: 5

    The half-diagonals are 3 and 4; side=sqrt(9+16)=5.

  4. A rectangle has perimeter 34 and area 60. What is the length of its diagonal?

    Answer: 13

    l+w=17 and lw=60 gives l=12,w=5; diagonal=sqrt(144+25)=13.

  5. What is the area of an equilateral triangle with side length 4?

    Answer: 4sqrt(3)

    Area=(sqrt(3)/4)*s^2=(sqrt(3)/4)*16=4sqrt(3).

  6. Two circles of radius 3 and 5 are externally tangent. What is the distance between their centers?

    Answer: 8

    For externally tangent circles, center-to-center distance=r1+r2=3+5=8.