Answer:
您能再解釋一下嗎,謝謝
Step-by-step explanation:
Answer:
see explanation
Step-by-step explanation:
Under a rotation about the origin of 90°
a point (x, y ) → (- y, x ), thus
A(2, 2 ) → A'(- 2, 2 )
B(2, 4 ) → B'(- 4, 2 )
C(4, 6 ) → C'(- 6, 4 )
D(6, 4 ) → D'(- 4, 6 )
E(6, 2 ) → E'(- 2, 6 )
Answer:
17
Step-by-step explanation:
Let us suppose two years ago my brother's age was x years
Then, my age was 3x
Three years from now, my brother's age will be (x +2+3) = (x+5) years
And my age will be (3x+2+3) = (3x+5) years
But it is given that i will be twice as old as my brother.
So, 2(x+5)= (3x+5)
or, x= 5 years
So my brother's present age is 5+2= 7 years
And my age is 5*3+2= 17 years
The Intersecting Secant Theorem says
EC × ED = EB × EA
(x+4)(x+4+1) = (x+1)(x+1+11)
(x+4)(x+5)=(x+1)(x+12)
x^2 + 9x + 20 = x^2 + 13 x + 12
8 = 4x
x = 2
Check:
6(7)=42
3(14)=42, good
Answer: 2