Geometric triangle questions, geometric questions about regular triangles

A, in the triangle ABP, bp sinbap=ab sinapb, so ab bp=sinapb sinbap

In the triangle ACP, cp sincap=ac sinapc, so ac cp=sinapc sincap;

again apb=apc, sinbap=sincap, so ab bp=ac cp is bp pc = ab ac

b, ab=25, ac=15, ab ac=5 3, so p((5(-15)+3) 8,(5(-19)+3(-7)) 8).

i.e. p(-9,

Your question doesn't seem to be right, the angle bap = angle cpa can't push out ap is the angle bisector of the angle bac, i think it should be bap = cap

Draw a triangle, then take any side and make parallel lines over the diagonal point of that side.

According to. The axiom that two straight lines are parallel and the inner angles are equal can get the inner wrong angles that are equal to the two bottom angles, and the sum of the inner wrong angles and the top angles is a straight line, and the straight line is 180 degrees, so the sum of the inner angles of all triangles is 180 degrees.

It is also not always 180 degrees, and there may be different results in different geometries.

There are currently three recognized geometric systems:

Euclidean geometry, Lobachevs-Bowyer geometry, and Riemannian geometry, the only difference between these three geometries is the difference in the fifth postulate. The fifth axiosum of Euclidean geometry refers to the fact that there is one and only one straight line parallel to a known straight line at a point outside the straight line. Roche geometry, on the other hand, stipulates that there are an infinite number of straight lines parallel to the known straight lines at a point outside the line.

In this way, the sum of the inner angles of the triangle is less than 180 degrees.

Riemann unified three geometries from a higher perspective, known as Riemann geometry. In non-Euclidean geometry, there are many strange conclusions. The sum of the internal angles of the triangle is not 180 degrees (the sum of the internal angles of the triangle in Riemannian geometry is greater than 180 degrees), and the pi is not so and.

Therefore, when it was first introduced, it was ridiculed and considered the most useless theory. It was not until its application was discovered in spherical geometry that it was taken seriously.

If there is no matter in space, space-time is straight, and Euclidean geometry is sufficient. For example, the application of special relativity is the four-dimensional pseudo-Euclidean space. A pseudo-word is added because there is an imaginary unit i. in front of the time coordinates

When there is matter in space, the matter interacts with space-time, causing space-time to bend, which is to use non-Euclidean geometry.

You are asking about the sum of the internal angles of a triangle in Euclidean geometry that is 180 degrees.

The answer is 1 9, because the height and bottom of the shaded part are both 1 3 of the height and bottom of the triangle, so 1 3 times 1 3

It's hard, but you can count the grids.

Because it is folded in half along the CD.

So the ADC is congruent with the EDC.

So ce=ac=3

And because E is the midpoint of BC.

So bc=6

The distance from D to the BC side is the distance from D to CE.

From congruence, the distance from d to ce is equal to the distance from d to ac (let the distance be h) The area of ACD = H·AC2=3H2

Area of BCD = H·BC2 = 6H2

So h=2 i.e. the distance from d to bc is 2

I only thought of the baa proof of the first one:

bad=∠1∠dac=∠2

bcd=∠3

dcn=∠4）

Ad is the angular bisector of the bac.

de⊥am∠dea=90°

1+ ade+ dea=180°

1+∠ade+90°=180°

an⊥l∠acb=90°

As can be seen from the figure, ACB and BCN are adjacent complementary angles.

bcn=90°

CD is the angular bisector of BCN.

2+ ACB+ 3+ ADC=180°, ACB=90° 2+90°+45°+ ADC=180° and 1+ ADE+90°=180°

1+ ADE+90°= 2+90°+45°+ ADC again 1= 2