please help me I'll mark brainliest 15 point or more plezzz

Answer:
The answers are:
a) x = -39/2
b) x = 30
c) x = 5
Explanation:
a) -3/4 = x/26 clear x
x = -3(26)/4
x = -78/4 = -39/2 solve
b) x/15 = 20/10 clear x
x = 20(15)/10 solve
x = 300 /10 = 30
c) x/25 = 3/15 clear x
x = 3(25)/15 = 75/15 = 5 solve