Find the sum or difference
1.) (x^2-3x+7) - (2x^2-6x+8)

2.(x^3+2x^2+12) + (9-3x^3+4x)

e

step-by-step explanation:

an equation by definition has to have two or more variables (x and 2 in this case)

statement #3: proof- ang is congruent to ang ecd : angles are congruent.  

step-by-step explanation:

1: the missing angles in statement #3  

a.) acb  

reason- the reason why the answer is acb is because angle ecd and angle acb are both the same size *that's what the word congruent means this is really simple.  

2: the missing word in reason #3  

c.) vertical  

reason- the reason why the answer is vertical is because the angles in that diagram on figure 2 is slanted, which is vertical, and the e and a both lay on vertical lines. along with the other's, but e and a are the 2 main points you want to focus on. and c is kind of like your starting point, because c is for both angles, not just one.  

i hope that was and understanding.

hello there!

i believe the answer is

(cot2+1)/sec2=cot2

    csc2/sec2=cot2

  (1/sin2)/(1/cos2)=cot2

  (1/sin2)(cos2/1)=cot2

  cos2/sin2=cot2

  (1/tan2)=cot2

  (cot2)=(cot2)

hope this !

hyperz ^_^