Question

Using the quadratic formula to solve x2 = 5 – x, what are the values of x?

Answer 1

Choice A is correct answer.

Explanation:

we have given equation.

x²= 5 - x

Above equation in standard form:

x² +x - 5 = 0

ax²+bx+c = 0 is general quadratic equation.

we solve this equation by using quadratic formula.

quadratic formula: (-b±√b²-4ac) / 2a.

In this equation, a = 1 , b = 1 ,c = -5.

Putting these values in above quadratic formula we have:

x = (-1±√(1)²-4(1)(-5) ) / 2(1)

x = (-1±√1+20) / 2

x = (-1±√21) / 2 which is the answer.

Answer 2

Hey there!

`\bold{x^2=5-x}`

• Firstly, add the "x" value on each of your sides
• 
  `\bold{x^2+x=5-x+x}`
• Simplify that part of your equation
• We get:
  `\bold{x^2+x=5}`
• Now we have to subtract by the number 5 on each of your sides
• 
  `\bold{x^2+x-5=5-5}`
• Simplify that part of the equation as well
• We get:
  `\bold{x^2+x-5=0}`
• USE THE QUADRATIC FORMULA TO MAKE IT EASIER TO SOLVE
• 
  `\boxed{\boxed{\bold{Answer:x=(-1+√(21))/(2);x=(=1-√(21) )/(2)}}}` (A)