SOLUTION: How would you find the product and simplify the following: (2a+5)^3 (the up arrow meaing the the power of 3) thank you

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: How would you find the product and simplify the following: (2a+5)^3 (the up arrow meaing the the power of 3) thank you      Log On


   

Question 429598: How would you find the product and simplify the following:
(2a+5)^3
(the up arrow meaing the the power of 3)
thank you
Found 2 solutions by Gogonati, ewatrrr:
Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
Solution:We apply the formula:%28x%2By%29%5E3=x%5E3%2B3x%5E2y%2B3xy%5E2%2By%5E3
Where,x=2a, and y=5. Substitute:
%282a%2B5%29%5E3=%282a%29%5E3%2B3%282a%29%5E2%2A%285%29%2B3%282a%29%2A5%5E2%2B5%5E3, simplify:
%282a%2B5%29%5E3=8a%5E3%2B60a%5E2%2B150a%2B125.
Done.

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

(2a+5)^3

(2a+5)(2a+5)(2a+5)

(2a+5)(4a^2 + 20a + 25)

2a(4a^2 + 20a + 25) + 5(4a^2 + 20a + 25)

 8a^3 + 60a^2 + 150a + 625



CHECKING our Answer***with the bionomial expansion formula for n=3

In General: (x+y)^3 = x^3 + 3(x^2)y + 3xy^2 + y^3



 (2a+5)^3 = (2a)^3 + 3(2a)^2*5 + + 3(2a)(5^2) + 5^3 

               8a^3  + 60a^2     + 150a       + 625