Question

AC=AD,BC=BD. найдите угол BAC если угол BAD=25°​

Answer 1

Ответ:

тоже 25°

Объяснение:

ΔАСВ=ΔАDВ,

∠САВ=∠DАВ=25°.

Answer 2

To find the value of angle BAC, we can use the fact that AC = AD and BC = BD. Since AC = AD, triangle ACD is an isosceles triangle, and since BC = BD, triangle BCD is also an isosceles triangle.

Given that angle BAD = 25°, we can find the value of angle BAC using the properties of isosceles triangles.

Step 1: Find the value of angle CAD (since triangle ACD is isosceles). Step 2: Find the value of angle BCD (since triangle BCD is isosceles). Step 3: Find the value of angle BAC.

Step 1: Since triangle ACD is isosceles, we have angle CAD = angle ACD. Let's assume the value of angle CAD = x (in degrees). Therefore, angle ACD = x degrees.

Step 2: Since triangle BCD is isosceles, we have angle BCD = angle BDC. And we know angle BAD = 25°. Since the angles in a triangle add up to 180°, we can find angle BCD: 180° - angle BAD - angle ACD = 180° - 25° - x = 155° - x degrees.

Step 3: Angle BAC is the exterior angle of triangle BCD. The sum of an exterior angle and an interior opposite angle in a triangle is 180°. So, angle BAC + angle BCD = 180°. Therefore, angle BAC = 180° - angle BCD.

Now we can substitute the value of angle BCD from Step 2 into the equation: angle BAC = 180° - (155° - x) = 180° - 155° + x = 25° + x degrees.

Finally, since we know that AC = AD, angle CAD = angle ACD = x, we can use the properties of triangles to find angle BAC: angle BAC + angle BAD + angle CAD = 180°. Therefore, we have: angle BAC + 25° + x = 180°.

Now, substitute the value of x from the previous equation (x = angle CAD = angle ACD): angle BAC + 25° + angle BAC = 180°. 2 * angle BAC + 25° = 180°.

Now, solve for angle BAC: 2 * angle BAC = 180° - 25°, 2 * angle BAC = 155°, angle BAC = 155° / 2, angle BAC = 77.5°.

So, the value of angle BAC is 77.5°.