I do not understand your language.i speak English. i am sorry i cannot help .HAPPY HALLOWEEN
Answer:
28.26
Step-by-step explanation:
A = pie x radius*2
The radius is 3, and pie is 3.14. This means the equation is
A = 3.14 x 3*2
3*2 is just 3 x 3, which is 9.
9 x 3.14 = 28.26
Every time, it increases by one and is multiplied by negative one
X + 3y = 9
3x - 3y = -13
--------------add
4x = - 4
x = -4/4
x = -1
x + 3y = 9
-1 + 3y = 9
3y = 9 + 1
3y = 10
y = 10/3
solution (-1,10/3)