In △ ABC, ∠ a = 90 ° and △ ABC rotates 45 ° counterclockwise around ∠ A. if AB = 3 and BC = 5, connect CC & # 185;, and calculate the area of △ ACC & # 185

In △ ABC, ∠ a = 90 ° and △ ABC rotates 45 ° counterclockwise around ∠ A. if AB = 3 and BC = 5, connect CC & # 185;, and calculate the area of △ ACC & # 185

AB = 3, BC = 5, so AC = 4 (Pythagorean theorem)
Naturally, AC1 equals 4
So △ ACC & # 185; is an isosceles triangle with a waist of 4 and a vertex angle of 45 degrees
From C to AC1
Because the apex angle is 45 and the waist is 4
So high 2 √ 2
So the area of △ ACC & # 185 = 4 * 2 √ 2 * 1 / 2 = 4 √ 2

As shown in the figure, in △ ABC, ∠ B = 90 °, C = 30 ° and ab = 1, rotate △ ABC 180 ° around vertex A and point C falls at C ', then the length of CC' is ()
A. 42B. 4C. 23D. 25

∵ in △ ABC, ∵ B = 90 °, C = 30 °, ab = 1, ∵ AC = 2. ∵ rotate △ ABC 180 ° around vertex a, and point C falls at C ', AC' = AC = 2, ∵ CC '= 4

AA + BB + CC = ABC, what are a, B and C respectively

ABC=198
Look at a bit: a + B + C, the result is C
So a + B = 10 (not equal to 0, not equal to 20)
By adding three two digit numbers, the result is also set within 300
So a = 1 or 2
When a = 1, B = 9, we can get C = 8
When a = 2, B = 8, there is no solution
So a, B and C are equal to 1, 9 and 8
In fact, AA + BB = 110 can be obtained from a + B = 10
And 110 + CC = ABC can already introduce a = 1, B = 9