Answer:
the distance formula is used to find the distance between two points in the plane. The Pythagorean Theorem, a2+b2=c2 a 2 + b 2 = c 2 , is based on a right triangle where a and b are the lengths of the legs adjacent to the right angle, and c is the length of the hypotenuse.
Step-by-step explanation:
 
        
             
        
        
        
The mathematical expression of the given complex number above is -5 + 4i. The conjugate of this complex number is that which has an opposite operation. The given is an addition operation. That is -5 - 4i. Therefore, the answer is the third among the choices. 
        
             
        
        
        
Answer:
56.5 inches
Step-by-step explanation:
You want to find the perimeter (or the length around the rectangle) to find much lace he needs. the formula for perimeter is 2L+2W=P. L being length, w being width and p being perimeter. Plug in the values for the equation and get 2(12.75)+2(15.5)=P. Multiply and get 25.5+31=56.5.
 
        
             
        
        
        
Answer:
   5.4 m
Step-by-step explanation:
The Pythagorean theorem tells you the relationship between the various lengths is ...
   cd² = ac² +ad²
   cd² = (2.4 m)² + (1.8 m)² = 9.00 m²
   cd = √(9.00 m²) = 3.0 m
Since cd = cb and ab = ac+cb, we have ...
   ab = 2.4 m + 3.0 m = 5.4 m
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You may recognize this as a 3-4-5 right triangle with a scale factor of 0.6. We are asked for the sum of the lengths of the "4" and "5" legs, which is ...
   0.6·(4+5) = 5.4