If x(5x -4)(x+3)(7x-2)= Ax^4 +Bx^3 +Cx^2 +Dx+E, find A+B+C+D+E. Please show me all of your work.

Question

myininaya · Answer

you should multiply all of that scary stuff out
$$x(5x^2+15x-4x-12)(7x-2)=x(5x^2+11x-12)(7x-2)=$$
$$=x(35x^3-10x^2+77x^2-22x-84x+24)=x(35x^3+66x^2-106x+24)$$
$$=35x^4+66x^3-106x^2+24x=35x^4+66x^3-106x^2+24x+0$$

myininaya · Answer

$$35x^4+66x^3-106x^2+24x+0=Ax^4+Bx^3+Cx^2+Dx+E$$

myininaya · Answer

so what is A
               B
               C
               D
               E
 ?

anonymous · Answer

A=35
B=66
C=-106
D=24
E=0
Is it right

myininaya · Answer

and then add them to find that sum! :)

anonymous · Answer

Is it 19

myininaya · Answer

35+66=101
         +   24
    ------------
            125

and 125-106=19
yep thats what I get :)

anonymous · Answer

I need to do a lot of practice. Thanks a lot for helping me.

myininaya · Answer

no problem.  i showed all the steps i would take in order to solve this problem. i hope it was  helpful.

anonymous · Answer

yes.It is.

myininaya · Answer

:) have a good day!

anonymous · Answer

Thanks again