It is known that in ABC, angle A is 45 degrees, angle B is 30 degrees, and AC is 10

Cause: ac sinb=bc sina so: bc=acsina sinb=10xsin45° sin30°=(10x 2 2) (1 2) =10 2

ab=ac+bc-2xacxbcxcosc c=180°-(a+b) So: ab=ac+bc-2xacxbcxcos(180°-(a+b)) =10+(10 2)-2x10x10 2x(-cos(a+b)) =100+200+200 2xcos(45°+30°))=300+200 2x(cos45°cos30°-sin45°sin30°) =300+200 2x( 2 2x 3 2- 2 2x1 2) =300+200 2x( 6 4- 2 4) =300+100 3-100 =200+100 3 So: ab=10 (2+ 3) The height on the BC side = absinb = 10 (2 + 3) xsin30° = 10 (2 + 3) x1 2 =5 (2 + 3).

BC sin45° = AC sin30° , BC = 10* (2 2) (1 2) = 10 2 Do the high AD on the side of BC, cross the extension line of BC with point D, then, ACD = 75°, sin75° = AD AC AD = 10sin75°=

Hello classmates, is this the topic? In the Pythagorean diagram on the right, it is known that the angle acb=90 degrees, the angle bac=30 degrees, ab=4, the cheat dry triangle pqr makes the angle r=90 degrees, the point h is on the edge qr, the point d, e is on the edge pr point g, f is on the edge pq, then the perimeter of apqr is equal to? Answer:

Extend the BA to the point m, connect the AR, AP leaser QHG is an equilateral triangle.

Angle A + Angle Royal Judgment Book B = 2 Angle C, that is, Angle A + Angle B = 2 (180-Angle A - Angle B) Angle Zhenhong A + Angle B = 360-2 Angle A - 2 Angle B

Angle a + angle b = 120

Angular impulse carrying a-angle b = 30 degrees.

So: angle a = 75 degrees.

Angle b = 45 degrees.

Angle c = 60 degrees.

b=180-45-30=105°

Because b sinb=c sinc

So b=sin105° sin30°*10, where sin105=sin(60+45)=sin60cos45+cos60sin45=( 6 2) 4

6 + 2) Lack of hunger 4] (1 2) * 105 ( Fu Zi Hui 6 + 2).

b=5 (Qi 6 + 2).

Similarly. a/sina=c/sinc

a=sin45°/sin30°*10

a=10√2

Because the old royal a+ 1=135 degrees [triangle inside the slippery angle and 180 degrees], and because a+15= 1 so the angle a=60 degrees, and because the handicap ACD=60 degrees, so ab is parallel to cd [the inner wrong angle is equal].

The perpendicular line of C is AB, and the perpendicular foot is D. The triangle is assigned to two right-angled triangles, then ad=1, cd= 3, and because of the envy hall dcb= b, dc=db= 3.

Foolishly, ab=1 + 3