In the triangle ABC, ab = C, AC = B, acute angle a = Alpha, problem (1) the length of BC
In ACD, sin alpha = CD / AC = CD / B, then CD = sin alpha * bcos alpha = ad / AC = ad / B, then ad = cos alpha * B, so DB = ab - ad = C - cos alpha * B in ACD
RELATED INFORMATIONS
- 1. Draw and fill in the blanks according to the following requirements: (1) draw a vertical line of line AC through point B, intersect line AC at point D, then the distance from point B to line AC is a line segment______ (2) make the vertical bisector EF of the side ab of △ ABC with a ruler and a compass, intersect the sides AB and AC at points m and N, and connect cm. Then the line segment cm is △ ABC______ (keep the trace of drawing)
- 2. [hope you can draw your own picture, thank you] in the triangle ABC, point D is on AC, point E is on AB, and ab = AC, BC = BD, ad = de = EB, find the degree of angle A
- 3. In the triangle ABC, ab = 5, the middle line ad = 7, draw a picture and determine the length range of AC side
- 4. Given the line segments a, B, m (a > b > m), find △ ABC, so that ab = a, AC = no, the middle line ad on the side of BC = M. how to draw, and what is the reason? Given the line segments a, B, m (a > b > m), find △ ABC so that ab = a, AC = B, ad = m on the edge of BC. What is the reason for how to draw? (correction)
- 5. In △ ABC, ab = AC, and the acute angle obtained by the intersection of the vertical bisector of AB and the line where AC is located is 50 °, then ∠ B is equal to______ .
- 6. It is known that in isosceles △ ABC, ab = AC. if the acute angle of the intersection of the vertical bisector of AB and the line of edge AC is 40 degrees, then the base angle of isosceles △ ABC ∠ B is 40 degrees______ .
- 7. In the triangle ABC, ab = AC, the acute angle obtained by the intersection of the vertical line of AB and the line where AC is located is 50 degrees, then the base angle B is
- 8. In △ ABC, ab = AC, and the acute angle obtained by the intersection of the vertical bisector of AB and the line where AC is located is 50 °, then ∠ B is equal to______ .
- 9. In △ ABC, ab = AC, and the acute angle obtained by the intersection of the vertical bisector of AB and the line where AC is located is 50 °, then ∠ B is equal to______ .
- 10. In the triangle ABC, ab = AC, the acute angle formed by the intersection of the vertical bisector of waist AB and the straight line AC is 50 ° and the intersection line AC is at point E, and the intersection line AB is at point D. calculate the degree of ∠ EBC
- 11. Given the line segments a, m, h, calculate △ ABC, such that BC = a, the height above it is h, and the central line of AC is m. (draw with ruler and compasses, and write the drawing steps)
- 12. As shown in the figure, given the line segments C and B (c > b), calculate: △ ABC, so that ∠ C = 90 °, ab = C, AC = B. (ruler drawing)
- 13. Given: line segments a and B, find: triangle ABC, so that ∠ C = 90 degrees, AC = a, BC = B
- 14. In the triangle ABC, ab = 10, BC = 16, ad = 6, then AC= I'm a wise man. If my questioning puzzles you, my IQ is 140
- 15. Known RT triangle ABC, angle c = 90 degrees, angle B = 30 degrees. 1, ruler drawing please God
- 16. In known RT triangle ABC, angle c = 90 degree, angle B = 30 degree
- 17. Given the line segments a, B and angle α, find the triangle ABC so that angle a = angle α, the opposite side of angle a is a and the other side is B Is there two ways to solve this problem? If so, please explain why
- 18. The angle β and the line segments a and B are known. How many triangles can be made by using a ruler to make the angle B = angle β, BC = a, AC = B? Angle β is an acute angle Line segment a is longer than B Better have a picture!
- 19. If the line segments a, ∠ a are known, find out the triangle ABC so that ∠ C = 90 °, AC = a, ∠ a = ∠ A. when drawing with ruler and gauge, trace is needed and urgent Be careful
- 20. Please use Boolean algebra to calculate and simplify 20 + 16