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In the triangle ABC, if the angle c + angle a = 2 angle B and the angle c-angle a = 80 °, then the angles a, B and C are respectively equal to? In the triangle ABC, the angle a is the minimum angle, the angle B is the largest angle, and the 2 angle B = 5 angle A. if the maximum value of angle B is m ° and the minimum value is n °, find m + n
Angle a is 20 degrees, angle B is 60 degrees, and angle c is 100 degrees
M + n is 175 degrees. Notice that this is the extreme value, not the maximum value. In fact, 75
In the triangle ABC, if the angle 1-angle B = 36 degrees, the angle c = 2 angle B, then what are the angles a, B and C equal to?
Angle 1 refers to angle A
From ∠ a - ∠ B = 36 °, we can get ∠ a = ∠ B + 36 °
And ∠ C = 2 ∠ B, and the sum of interior angles of triangle is 180 °
∴∠a+∠b+∠c=∠b+36°+∠b+2∠b=4∠b+36°=180°
∴∠b=36°
∴∠a=∠b+36°=72° ∠c=2∠b=72°
In the triangle ABC, the angle a is equal to three times the angle B, and the angle a minus the angle c is equal to 30 degrees? A mathematical problem, there is no diagram
a=3b
a-c=30
a+b+c=180
So a = 90
b=30
c=60
A: a = 90 °, B = 30 ° and C = 60 °
In triangle ABC, if angle a minus angle B equals angle c minus angle a, then what degree is angle a equal to
∠A-∠B=∠C-∠A
2∠A=∠B+∠C
∠A+∠B+∠C=180°
3∠A=180°
∠A=60°
In the triangle ABC, the angle c = 60 ° angle a minus angle B = 20 degrees. Then what is the angle B
Let the angles a, B and C be a, B and C respectively
c+a=180-b=2b
b=60
c-a=80
c=100 a=20
In the triangle ABC, angle a = angle B, 1 / 4 angle c = angle A. find the degree of each angle in the triangle
2 * 1 / 4
In the triangle ABC, if the angle a equals 100 degrees and the angle B minus the angle c equals 40 degrees, how many degrees is the angle c equal to
a+b+c=180
b+c=80
b-c=40
b=60 c=20
So the angle c is 20 degrees
It is known that in the triangle ABC, the angle a = 40 degrees, the angle B-angle C = 40 degrees? You don't have to write a process, but it's better to have a process,
Angle a + angle B + angle c = 180 degrees
Angle B-angle C = 40 degrees 2
It is obtained by adding Formula 1 and formula 2
Angle A+ angle B*2=220 degrees
Angle a = 40 degrees
So the angle B is 90 degrees
Angle c = 180 degrees - angle a - angle B = 50 degrees
As shown in the figure: given that the bisectors of the exterior angles of ∠ B and ∠ C of △ ABC intersect with D, ∠ a = 40 °, then ∠ D=______ Degree
Since the bisector of CD and BD intersects at point D, then ∠ 4 + ∠ 5 = 12 × 220 ° = 110 ° is determined according to the sum of inner angles of triangle
In the triangle ABC, the angle BAC is equal to 100 degrees, ab = AC, BD bisection angle ABC intersects AC with D, it is proved that BC = BD + da
Make two auxiliary lines, take a point E on the extension line of Ba, make be = BD, take a point F on BC, and make BF = BD. in this way, two isosceles triangles EBD and FBD are formed, and these two triangles are congruent. Therefore, if ed = DF and then prove FC = ad, it can be proved that BC = BD + ad. by calculating the angle, we can know ∠ FCD = ∠ FDC = 40 degrees ∠ DEA = ∠ E
RELATED INFORMATIONS
- 1. As shown in the figure, △ ABC ≌ △ ade, the corresponding vertex of point B is point D. if ∠ bad = 100 °, CAE = 40 °, calculate the degree of ∠ BAC
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