Step-by-step explanation:
1. You already got the first step, where D is the midpoint of AC and AB is congruent to BC, since it's given. 
2. AD will be congruent to DC, via the definition of a midpoint (a midpoint is the middle point of a line segment, and it splits the segment into two congruent parts) 
3. BD is equal to BD, via reflexive property. ( It's a shared side between the two triangles)
4. that means that ΔADB ≅ΔCDB via SSS rule. 
5. ∠ABD ≅∠CDB by CPCTC (corresponding parts of congruent triangles are congruent) 
Hope this helps! :) 
 
        
                    
             
        
        
        
Answer:
3/4-7/9+2/3=0.63
Step-by-step explanation:
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1/2 z = -3/4 + 1/4 z
1/2 z - 1/4 z = -3/4
1/4 z = -3/4
z = (-3/4)/(1/4)
z = -3/4 x 4/1
z = -3
        
             
        
        
        
Answer:
Mg/mi. A Company Has 16 Cars Of This Model In Its Fleet. ... The level of nitrogen oxides (NOX) and nonmethane organic gas (NMOG) in d ... organic gas (NMOG) in the exhaust over the useful life (150,000 miles of driving) of cars of a particular model varies Normally with mean 85 mg/mi and standard deviation 6 mg/mi.
Step-by-step explanation:
 
        
             
        
        
        
Answer: 0.5143
Step-by-step explanation:
Probability of students who are over 21 years old = 30% = 0.3
Probability of students who are under 21 years old = 100% - 30% = 70% = 0.7
Probability of drinking alcohol for over 21 = 80% = 0.8
Probability of not drinking alcohol for over 21 = 100%- 80% = 20% = 0.2
Let the probability of the students who are not over 21, that drink alcohol be p.
Total probability of a college student drinking alcohol = (0.3 × 0.8) + (0.7 × p)
0.6 = (0.3 × 0.8) + (0.7 × p)
0.6 = 0.24 + 0.7p
0.7p = 0.6 - 0.24
0.7p = 0.36
p = 0.36/0.7
p = 0.5143
The probability of the students who are not over 21, that drink alcohol is 0.5143.