Solve for a???

Question

9a^3-225a=0

i assume you factor out the 9, so it becomes

9(a^3-25)=0

but then what?

Answer 1

[07]
9a^3-225a=0
9a(a^2-25)=0
9a{(a)^2-(5)^2}=0
9a(a+5)(a-5)=0
Therefore, 9a=0 or a+5=0 or a-5=0
If 9a=0,then a=0
If a+5=0,then a= -5
If a-5=0,then a=5
a=0,-5 or 5 ans

Answer 2

9a^3 – 225a = 0
9 a ( a^2 – 25) = 0
9 a ( a + 5) (a – 5) = 0
Therefore 9 a = 0 or ( a + 5) = 0 or (a – 5) = 0
so a = 0 or a = 5 or a = – 5

Answer 3

9a^3-225a =0

It is better to take " a" common.

a(9a^2-225)=0

product of two numbers equal to 0 => either of them is 0 or both are 0

so, either a=0 or 9a^2-225=0
a^2 = 225/9
a^2 = 25
a = plus or minus 25.

so finally, a = 0 or a = -5 or a = +5

Answer 4

You factor out 9a so:

9a(a^2-25) ==> a = 0 or a = 5

Answer 5

Your question says solve for 'a', not simply/expand for 'a'

9a^3 - 225a = 0

9a^3 = 225a

a^3 = 25a

a^2 = 25

a = sqrt (25)

a = 5

Answer 6

you left out an 'a'. it is actually 9(a³-25a) so factor out an 'a' also. get 9a(a²-25) = 0
now when you multiply two things and you get 0, that means one of those things you multiplied by is equal to 0.
so either 9a = 0 OR a²-25 = 0
solve for both:
9a=0
a=0
OR
a²-25=0
a²=25
a=+/- 5
so...a=0, 5, or -5

Answer 7

9 a ( a ² - 25 ) = 0
9 a ( a - 5 )( a + 5 ) = 0
a = 0 , a = 5 , a = - 5

Answer 8

After you factor out the 9, you can divide both sides by 9, add 25 to both sides, and finally take the cube root of both sides. You get a = 25^(1/3), or 5^(2/3)