Answer:
12°
Step-by-step explanation:
Let's start with the easy first. 
We know that m∠C is 39° because together ∠C and the exterior angle equal 180°. And 180 - 141 = 39.
Now, we can use this to find the remaining two angles.
180° - 39° = 141°
So, this means that we can set up m∠A + m∠B = 141°.
6x + 9 + x - 8 = 141
7x + 1 = 141
7x = 140
x = 20
Finally, we can plug in for our x value and find m∠B.
m∠B = x - 8
m∠B = 20 - 8
m∠B = 12°
 
        
             
        
        
        
Answer:
9*(6+7)
Step-by-step explanation:
First, we have to find the Greatest Common Factor (GCF), to do this we have to see all the factors of 54 and 63 and find the greatest factor that they have in common.
Factors of 54
1,2,3,6,9,18,27,54
Factors of 63
1,3,7,9,21,63
The GCF is 9 because is the greatest factor that is common to both numbers. 
Now we have to divide 54/9 and 63/9
54/9 = 6
63/9 = 7
So now we can write the product of the GCF and another sum:
9*(6+7)
<em>We can prove this by solving both expressions:</em>
<em>54+63 = 9*(6+7)</em>
<em>117 = 9*13</em>
<em>117 = 117 </em>
<em>The results are equal so we prove it is right.</em>
 
        
                    
             
        
        
        
The answer is 15w^2 + 225w
Key:
^ - Means that it is an exponent, in case you didn't know :)
        
             
        
        
        
The answer for the 2nd one is c ur welcome btw idk what 1 is sry
        
             
        
        
        
The scale factor can change how big or small a figure is, though it will still be similar. For example, a triangle with two sides measuring 3 & 3 (isosceles) are scaled in a factor of 6 (becoming larger).
3 x 6 = 18
The new triangle will have the sides measuring 18. Even though the triangles are not congruent, they are similar.
hope this helps