How to find the least common denominator of 3 fractions?

  Find the LCD of the first two, then the LCD of that and the third one.

Step-by-step explanation:

You can do it by finding the LCD of two of the denominators, then the LCD of that and the third denominator.

Or, you can factor each of the denominators and find their LCM by multiplying the unique factors to their highest powers.

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Example:

  1/21 + 1/35 + 1/45

The LCD of 1/21 and 1/35 is (21·35)/5 = 105. The LCD of 1/105 and 1/45 is ...

  (105·45)/15 = 315

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Using factoring ...

LCD = 3²·5·7 = 315

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

answer:

f(5/2) = 10/3

i hope this you!

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.