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