Question

What is the first step in the solution of 3x2+6x=12 by completing the square?

Answer 1

• 3x²+6x=12

Divide all terms by a i.e 3

We get

• x²+2x=4

Or

• r²+2r=4

Option B is correct

Answer 2

Answer:

B: r² + 2r = 4

Explanation:

$\rightarrow \sf 3x^2+6x=12$

divide both sides by 3

$\rightarrow \sf x^2+2x=4$    ← This is the result of the first step.

factor out the common term

$\rightarrow \sf x(x+2) = 4$

set to 0

$\rightarrow \sf x = 4, \ x+2 = 4$

simplify

$\rightarrow \sf x = 4, \ x= 2$