Answer :

Answer:

Step-by-step explanation:

1)

a/c =b/d  where a=27 c=30 b=x d=18

27/30 = x/18

27*18/30=x

16.2 = x

2)

a/c =b/d  where a=2x-5 c=x+11 b=16 d=14

2x-5 / x + 11  = 16 / 14

14(2x-5) = 16(x+11)

28x - 70 = 16x + 176

12x = 246

x = 20.5

3)

6+15 / 7+x  = 7 /6

6(6+15) = 7(7+x)

6*21 = 49 +7x

126 = 49 +7x

77 = 7x

11 = x

4)

3*[(x-6)+3]=[tex]6^{2}[/tex]

3(x-3) = 36

3x-9 = 36

3x = 45

x = 15