200.............................................................
A = bc/2 - bd/2
bd/2 = bc/2 - a
bd = bc - 2a
d = (bc - 2a)/b
X^2 + 3 - 3 + x = 0
x^2 + x = 0
x (x + 1) = 0
1) x = 0;
2) x + 1 = 0
x = - 1
Ответ
- 1; 0
6x-2y-5=2x-3y
6x-2x-2y+3y=5
4x+y=5
4x=5-y
x=5-y/4
5-x+2y=4y+16
-x+2y-4y=16-5
-x-2y=11
-(5-y/4)-2y=11
(-5+y/4)-2y=11
-5+y-8y=44
-7y=44+5
-7y=49
y=-7
x=5-(-7)/4=12/4=3
Ответ: (3;-7)