Question

Himpunan penyelesaian dari sistem persamaan x -y =5 dan x² -y² =45 adalah

Answer 1

X - y = 5
x = 5 + y

x² - y² = 45
(5+y)² - y² = 45
25 + 10y + y² - y²= 45
10y = 20
y = 2

x = 5 + y = 5+2= 7

Hp (7,2)

Answer 2

x - y = 5
x² - y² 45
(x - y) (x + y) = 45
      5 (x + y)  = 45
            x + y = 45 : 5
            x + y = 9
x + y = 9
x -  y = 5
---------------- +
2x     = 14
      x = 14 : 2
      x = 7
x + y = 9
7 + y = 9
      y = 9 - 7
      y = 2
Hp = (7 , 2)