soal ujian semester

1.Determine the values of X, Y, and Z that fulfill the equation system of :
1/x+1/y+1/z=10
2/x+1/y-1/z=2
3/x+4/y+2/z=4

2.Two years ago, a man’s age was 6 times of his child’s age, the next 18 years, his age is twice as his child’s age. Find out their age of present. Determine the solution of :
a. 1/2 x+1≤1/4 x+2
b. (x+5)(3x-5)<0
c. (x-3)/(x+5)≥0
d. √(x-1) < √(3-x)
3.A piece of wire x cm long will be shaped a rectangular. With the length measurement is twice of the width measurement. If the area of the formed rectangular is greater than it’s circumference. Find out the fulfilled length of the wire.
Determine the truth-value of the following statement
a. 4 Prime numbers and 5 whole numbers
b. 17 is not a prime number or 17 is not divisible by 3
c. If Jakarta is Bali island then Jakarta is the capital of Republic of Indonesia
d. AC = BD if and only if ABCD is a rectangular