+0

# help! How to,do efficiently?

0
251
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123456789^2-2*123456789*123456787+123456787

Jun 16, 2019

#1
+21955
0

123456789^2-2*123456789*123456787+123456787 =  -15241578132906578   by copy and paste into web2.0 calculator

Jun 16, 2019
#2
0

I don’t think that’s correct. Help!

Jun 16, 2019
#3
+195
+1

\(123456789^2-2*123456789*123456787+123456787\)

x=123456789

Rewrite this as:

x^2-2x(x-2)+x-2

(123456787 is 2 less that 123456789 so it can be written as x-2)

Now simplify the equation:

x^2-2x^2+4x+x-2         distribute -2x

-x^2+5x-2                    combine like terms

That can't be factored so I guess that would be as simple as you can get it.

Doing the problem this way would be marginally more efficient, but I still wouldn't want to do that by hand. The problem looks like it is set up to be solved how I solved it, but the numbers didn't work out very well.

Jun 16, 2019
#4
0

(123456789^2) - ((2*123456789*123456787)+123456787)

123456789^2 = 1524157 8750190521................................................................(1)
2*123456789*123456787+123456787 = 3048315 7130010673.......................(2)
Subtract (2) from (1):
15,241,578,750,190,521 - 30,483,157,130,010,673
=-15,241,578,379,820,152

Jun 16, 2019
#5
+8873
+2

Is the question supposed to be this:

1234567892  -  2 * 123456789 * 123456787  +  1234567872

???

Jun 16, 2019
#6
+1

Yes. So sorry for the typo. My apologies

Jun 17, 2019
#7
+8873
+2
Jun 17, 2019
#8
+7764
0

1234567892  -  2 * 123456789 * 123456787  +  1234567872

= (123456789 - 123456787)2

= 22

= 4

Jun 22, 2019