Question #e198c

2 Answers
Jan 17, 2018

just solve...

Explanation:

so
150x+70100x15+45018=12

50x+55+450=30

50x=42055

x=47550=192

hope u find it helpful :)

Jan 19, 2018

Assumption: The question is 50(3x+752x310+9)18=12

x=192

A lot of detail given so you can see where everything comes from. Get used to these and you will start to jump steps and be much faster.

Explanation:

Collecting like terms:

50(3x2x+75310+9)18=12

50(x+75310+9)18=12
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Consider inside the brackets

Multiply by 1 and you do not change the value. However 1 comes in many forms.

x+75310+9ddddddx+[75×1]310+[9×1]

dddddddddddddddddddx+[75×22]310+[9×1010]

dddddddddddddddddddx+dd1410ddd310+dd9010

dddddddddddddddddddx+10110
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Putting it all back together

50(x+10110)18=12

Add 18 to both sides- moves it to the right of =

50(x+10110)18+18=12+18

50(x+10110)+dd0dd=30

Multiply everything inside the brackets by 50

50x+505=30

Subtract 505 from both sides - moves it to the right of =

50x=475

Divide both sides by 50 moves it to the right of =

5050x=47550

But 5050 is the same as 1 and 1×x gives just x

x=475÷550÷5=95÷510÷5=192

19 is a prime number so we can not simplify any further.
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Foot note

First few prime numbers:
2; 3; 5; 7; 11; 13; 17; 19; 23 ........
Worth committing to memory all the primes up to and including 101