Y=2x+3y=-x+3
y=3y+2x=-x+3
y=3y+2x та 3y+2x=-x+3
y=-x та y=-x+1
1) 2x + 3y = 3 | 5 10x + 15y = 15
+
5x - 4y = 19 | - 2 - 10x + 8y = - 38
_______________
23y = - 23
y = - 1
2x + 3 * (-1) = 3
2x - 3 = 3
2x = 6
x = 3
Ответ: (3 ; - 1)
2) a + b = 22
+
a - b = 3
_________
2a = 25
a = 12.5
12,5 + b = 22
b = 22 - 12,5
b = 9,5
(5х+3)(5х+3)-(5х-3)(5х-3)/х
25х²+30х+9-(25х²-30х+9)/х
25х²+30х+9-25х²+30х-9/х
60х/x
=60 Наверное так)
D=(a15-a6)/(15-6)=(-12,6+5,4)/9=-7,2/9=-0,8