SOLUTION: Solve for F: C=5/9(F-32) please explain process thanks

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Question 164010: Solve for F: C=5/9(F-32)
please explain process thanks
Found 2 solutions by orca, jojo14344:
Answer by orca(409) About Me  (Show Source):
You can put this solution on YOUR website!
C=%285%2F9%29%28F-32%29
9C=9%2A%285%2F9%29%28F-32%29 (multiply both sides by 9 to clear the denominator)
9C=5%28F-32%29
9C%2F5=5%28F-32%29%2F5 (divide both side by 5)
%289%2F5%29C=F-32
%289%2F5%29C%2B32=F-32%2B32 (add 32 to both sides)
%289%2F5%29C%2B32=F
So
F=%289%2F5%29C%2B32

Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!
We can also use slope-intercept form to prove the above eqn
Y%5B2%5D-Y%5B1%5D=m%28X%5B2%5D-X%5B1%5D%29
where,
Y=Fahrenheit ---system%28Y%5B2%5D=boiling=212F%2CY%5B1%5D=freezing=32F%29
X=Celsius --- system%28X%5B2%5D=boiling=%28100%5Eo%29C%2CX%5B1%5D=freezing=%280%5Eo%29C%29
Substituting,
212-32=m%28100-0%29
180=m%28100%29 ----> 180%2F100=m%2Across%28100%29%2Fcross%28100%29
highlight%28m=1.8=9%2F5%29
So, Y%5B1%5D & X%5B1%5D given, and designate Y%5B2%5D=F. Also X%5B2%5D=C
it follows,
F-32=%289%2F5%29%28C-0%29
F-32=%289%2F5%29%28C%29
%28F-32%29%2F%289%2F5%29=cross%289%2F5%29C%2Fcross%289%2F5%29
highlight%28C=%285%2F9%29%28F-32%29%29
Also,
%28F-32%29=%289%2F5%29%28C-0%29, transpose to right term "32" fo find F
highlight%28F=%289%2F5%29%28C%29%2B32%29
Thank you,
Jojo