Given 25x^2 - 10x = 0, which values of x will satisfy the equation? (Hint: Factor the polynomial into two terms, and find the values of x that will make each term 0.)

A. x = 0 and x = 5/2

B. x = 0 and x = 2/5

C. x = 0 and x = 2

D. x = 0 and x = 5

4 answers

Improvement over your last post.

25x^2 - 10x = 0
5x(5x-2) = 0

5x = 0 ---> x=0
or
5x-2=0 ---> x = 5/2
x= 0

x = 2/5 not 5/2

Reiny is wrong
5x-2 = 0

5x= 2

x = 2/5
Obviously x = 0

25 x ^ 2 - 10 x = 0

25 * 0 ^ 2 - 10 * 0 = 0

25 * 0 - 10 * 0 = 0

0 - 0 = 0

0 = 0

and

25 x ^ 2 - 10 x = 0 Divide both sides by 5 x

25 x ^ 2 / 5 x - 10 x / 5 x = 0 / 5 x

5 * 5 * x * x / 5 x - 2 * 5 x / 5 x = 0

5 x - 2 = 0 Add 2 to both sides

5 x - 2 + 2 = 0 + 2

5 x = 2 Divide both sides by 5

5 x / 5 = 2 / 5

x = 2 / 5

B. x = 0 and x = 2 / 5