only number one please help

Answer:
C) 75 + 50x = 25 + 70x
Step-by-step explanation:
ABC Tech:
$50 an hour. So,for x hours= 50 * x = 50x
Service charge = 75 + 50x
Tech Squad:
$70 an hour. So,for x hours= 70 * x = 70x
Service charge = 25 + 70x
C) 75 + 50x = 25 + 70x
50x - 70x = 25 - 75
-20x = -50
x = -50/-20
x =5/2 = 2[tex]\frac{1}{2}[/tex]hours