Question

As soluções da equação 2X² - 7 = 7 (x-1) + 2x são:

{A) x= 2 ou x= 7}
{B) x= 0 ou x= 2}
{C) x= 0 ou x= 9}
{D) x= 2 ou x= -7/2}
{E) x= 0 ou x= 9/2}

Answer 1

E) x= 0 or x= 9/2

Explanation:

You have the following equation:

`2x^2-7=7(x-1)+2x` (1)

In order to find the solutions for x of the equation (1), you simplify it and factorize in a convenient way, as follow:

`2x^2-7=7x-7+2x\\\\2x^2-9x=0\\\\x(2x-9)=0` (2)

Then, by the previous factors, it is necessary that either x=0 or 2x-9 = 0.

Thus, one of the solution is x=0. The other solution is:

`2x-9=0\\\\x=(9)/(2)`

Hence, the solutions of the equation (1) are:

E) x= 0 or x= 9/2