SOLUTION: hi kindly help me pls Let g(x)=9x/10 - 8/9   and find the value of x that corresponds to g(x)=7/8 x=? Thanks   .

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Question 1160238: hi
kindly help me pls
Let g(x)=9x/10 - 8/9
 
and find the value of x that corresponds to g(x)=7/8
x=?
Thanks
 
.

Found 2 solutions by greenestamps, MathLover1:
Answer by greenestamps(13195) About Me  (Show Source):
You can put this solution on YOUR website!


9x%2F10-8%2F9=7%2F8

Note before we start working on solving this, the denominators 10, 9, and 8 mean the answer is probably not going to be a "nice" fraction....

Multiply by a common denominator, 8*9*10 = 720. (We could spend some time to find the LEAST common denominator; but the amount of simplification of the calculations would probably not be worth the time and effort.)

72%289x%29-80%288%29+=+90%287%29
648x-640+=+630
648x+=+1270
x+=+1270%2F648

Simplify the fraction or convert to decimal if desired or required.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

+g%28x%29=9x%2F10+-+8%2F9+
 
the value of x that corresponds to g%28x%29=7%2F8+ will be:

+7%2F8=9x%2F10+-+8%2F9+.......solve for x
.
+7%2F8%2B8%2F9=9x%2F10++

+%287%2A9%29%2F%288%2A9%29%2B%288%2A8%29%2F%289%2A8%29=9x%2F10++

+127%2F72=9x%2F10++.......both sides multiply by 10

+10%28127%2F72%29=9x++

+1270%2F72=9x++......both sides divide by 9

+1270%2F%289%2A72%29=x++.........simplify

+x=635%2F324+->exact result

+x=+1.9598765432+-. approximately