1. bila x-x/y = 3 dan x=5, maka y =...??? 2. (x+y) pngkt 2 - 36 = 0 dan xy =8, maka x pngkt 2 + y pngkt 2 = ....?? 3. bila x + y = 16 maka 1/4x + 1/4y adalah..?

1]x - x/y = 3 ; x = 5
x - x/y = 3
5 - 5/y = 3
5/y = 5 - 3
5/y = 2
y = 5/2
y = 2,5

2](x + y)^2 - 36 = 0 ; xy = 8
(x + y)^2 - 36 = 0
(x + y)^2 = 36
x + y = akar 36
x + y = 6
x = 6 - y
xy = 8
(6 - y)y = 8
6y - y^2 = 8
y^2 - 6y + 8 = 0
(y - 4)(y - 2) = 0
y - 4 = 0 atau y - 2 = 0
y = 4 atau y = 2
xy = 8
x(4) = 8 atau x(2) = 8
x = 8/4 = 2 atau x = 8/2 = 4
(2,4) atau (4,2)

.................x^2 + y^2
= 2^2 + 4^2 atau = 4^2 + 2^2
= 4 + 16.........atau = 16 + 4
= 20...............atau = 20

3] x + y = 16
1/4 x + 1/4 y = 1/4(x + y)
.......................= 1/4 × 16
.......................= 16/4
........................= 4

4]0,005 × 5.000 × 50.000 = 5^3 × 10^3 × X
1.250.000 = 125.000X
X = 1.250.000/125.000
X = 10