Answer:
The answer is 21
Step-by-step explanation: You substitue 3 for C and 4 for D and craete the equation  so you add 3+4=7 and you get
 so you add 3+4=7 and you get  which is 7 times 3 =21
 which is 7 times 3 =21
 
        
             
        
        
        
Answer:
Ваша глупость
Step-by-step explanation:
 
        
             
        
        
        
Answer: 12.25
Step-by-step explanation:
Given the following details :
DAC = 90° and ABC = 90° = right angled
Segment AB is Parallel to segment DC
FROM THE DETAILS ;
Triangle ABC and ACD are similar triangles. 
Length AC = 7 Units 
Length AB = 4 Units 
For similar triangles :
Segment CD /AC = Segment AC / AB
CD / 7 = 7 / 4
Cross multiply 
CD × 4 = 7 × 7
CD × 4 = 49
CD = 49 / 4
CD = 12.25 Units 
 
        
             
        
        
        
Answer:
572.5
Step-by-step explanation:
A=6ah + 3√(3) a²= 6·8·5+3√(3)·8²≈572.55376
a is base length and h is height
 
        
             
        
        
        
1) a. x = number of cars
b. x - 12
2) a. x = number of packages 
b. 16 + 1/2x
3) a. x = number of coins
b. 1/2x - 6
4) 17 + x = 78
Subtract 17 from each side. 
x = 61
5) x - 33 = 78
Add 33 to each side. 
x = 111
6) x * 84 = 327.6
Divide each side by 84
x = 3.9
7) 1333/8.6 = 155
The speed was 155mph. 
8) 2475/110 = 22.5
The trip took 22 and a half hours. (Or "The trip took 22.5 hours."