7. Straight lines are also = to 180°
If you look at the diagram, when you add the two angles together, they form a straight line.
Since the angles add up to 180°, you can do:
(x + 25)° + (4x + 5)° = 180°
x + 25 + 4x + 5 = 180        Combine like terms
5x + 30 = 180         Subtract 30 on both sides
5x = 150       Divide 5 on both sides
x = 30
 
        
             
        
        
        
Answer:
-142
Step-by-step explanation:
First solve parenthesis,
(12) - (23 +131) =
(12) -154
Finally subtract,
12-154 
= -142
 
        
             
        
        
        
Answer:
There are 48 marbles in the bag
Step-by-step explanation:
red: blue : total
3                   8
there are 18 red
18/3 = 6
Multiply everything by 6
3*6                 8*6
18                    48
There are 48 marbles in the bag
 
        
             
        
        
        
Answer: 49
Step-by-step explanation:
The missing constant term in the perfect square is 49.
x^2 + 14x + 49
We need a squart root of something to make the factor add up equal to 14x. If it's a perfect square, we could divide 14 by 2, 14/2 = 7, and we multiply 7^2, we get 49, which is a perfect square. 
 
        
             
        
        
        
Decrease 11.11% 
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