Answer: What is the complete question? Can you comment it?
Step-by-step explanation: I can’t help unless I know what the full question is. Sorry.
 
        
             
        
        
        
Answer:
Step-by-step explanation:
 Look for the GCF and then divide every term by the GCF to see what remains
(9) 5a - 25  ( GCF is 5 so take out 5 and divide every term by 5)
      5(a-5)
(10) 28 - 7x     ( GCF is 7 so take out 7 and divide every term by 7)
      7(4-x)
(11) 12z + 28 - 7z - 3=  (combine terms) = 
        5x+25( GCF is 5 so take out 5 and divide every term by 5)
         5(x+5)
 
        
             
        
        
        
Answer:
(-1, -1/2)
Step-by-step explanation:
M= (Xa+Xb/2, Ya + Yb/2)
M= -11+9/2  ,  0 + -1/2
M = -2/2, -1/2
M=(-1, -1/2)
 
        
                    
             
        
        
        
The area bounded by the 2 parabolas is A(θ) = 1/2∫(r₂²- r₁²).dθ between limits θ = a,b... 
<span>the limits are solution to 3cosθ = 1+cosθ the points of intersection of curves. </span>
<span>2cosθ = 1 => θ = ±π/3 </span>
<span>A(θ) = 1/2∫(r₂²- r₁²).dθ = 1/2∫(3cosθ)² - (1+cosθ)².dθ </span>
<span>= 1/2∫(3cosθ)².dθ - 1/2∫(1+cosθ)².dθ </span>
<span>= 9/8[2θ + sin(2θ)] - 1/8[6θ + 8sinθ +sin(2θ)] .. </span>
<span>.............where I have used ∫(cosθ)².dθ=1/4[2θ + sin(2θ)] </span>
<span>= 3θ/2 +sin(2θ) - sin(θ) </span>
<span>Area = A(π/3) - A(-π/3) </span>
<span>= 3π/6 + sin(2π/3) -sin(π/3) - (-3π/6) - sin(-2π/3) + sin(-π/3) </span>
<span>= π.</span>