Question

What is the first step in solving the quadratic equation -5x2+8=133?

a. taking the square root of both sides of the equation
b. subtracting 8 from both sides of the equation
c. squaring both sides of the equation
d. adding 8 to both sides of the equation

Answer 1

b. The first step in the equation solving is subtracting 8 from both sides of the equation.

Explanation:

Here, the given quadratic equation is :
`-5x^2 + 8  = 133`

Let us try and solve this given equation.

`-5x^2 + 8  = 133 \\\implies -5x^2 + 8  - 8 = 133 -8\\\implies  -5x^2  =  125\\\implies  x^2  =(125)/(-5)  = -25\\\implies x^2  = -25 = (5i)^2`

So, x = ± 5i

Hence, as we can see here, the first step in the equation solving is subtracting 8 from both sides of the equation.