Step 1 :
After factoring out $ 2 $ we have:
$$ 250m^{3}+54 = 2 ( 125m^{3}+27 ) $$Step 2 :
To factor $ 125m^{3}+27 $ we can use sum of cubes formula:
$$ I^3 - II^3 = (I + II)(I^2 - I \cdot II + II^2) $$After putting $ I = 5m $ and $ II = 3 $ , we have:
$$ 125m^{3}+27 = ( 5m+3 ) ( 25m^{2}-15m+9 ) $$Step 3 :
Step 3: Identify constants $ a $ , $ b $ and $ c $.
$ a $ is a number in front of the $ x^2 $ term $ b $ is a number in front of the $ x $ term and $ c $ is a constant. In this case:
Step 4: Multiply the leading coefficient $\color{blue}{ a = 25 }$ by the constant term $\color{blue}{c = 9} $.
$$ a \cdot c = 225 $$Step 5: Find out two numbers that multiply to $ a \cdot c = 225 $ and add to $ b = -15 $.
Step 6: All pairs of numbers with a product of $ 225 $ are:
PRODUCT = 225 | |
1 225 | -1 -225 |
3 75 | -3 -75 |
5 45 | -5 -45 |
9 25 | -9 -25 |
15 15 | -15 -15 |
Step 7: Find out which factor pair sums up to $\color{blue}{ b = -15 }$
Step 8: Because none of these pairs will give us a sum of $ \color{blue}{ -15 }$, we conclude the polynomial cannot be factored.