Which of the following correctly completes the square for the equation below?

x^2+2x=19
a. (x+2)^2=20
b. (x+1)^2=23
c. (x+1)^2=20
d. (x+2)^2=23

c.

Step-by-step explanation:

Since, for getting a perfect square on the left side of a quadratic equation we follow the following steps,

Step 1 : Make 1 as the coefficient of .

Step 2 : Add both side the square of a number which is half of the x's coefficient.

Given equation,

-----(1)

Here, the coefficient of is already one.

And, the middle term is 2,

Half of 2 is 1

Also, 1² = 1

Thus, add 1 on both sides of equation (1),

   ( Because (a+b)² = a² + 2ab + b² )

⇒ Option C is  correct.

the ratio of balloons to tables is 5: 2 and the constant variation is 5.

the equation is y=5x