McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
Study Guide and Review
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Exercise 36 Page 159

To complete the square, make sure all the variable terms are on one side of the equation. Then, divide both sides of the equation by a so that the coefficient of x^2 is 1.

1.2 and - 1.2

Practice makes perfect
We want to solve the quadratic equation by completing the square. To do so, we will start by rewriting the equation so all terms with x are on one side of the equation and the constant term is on the other side. -3x^2+4=0 ⇓ -3x^2=-4 Now, let's divide each side by -3 so that the coefficient of x^2 will be 1.
-3x^2=-4
-3x^2/-3=-4/-3
Simplify
3x^2/3=4/3
3/3x^2=4/3
1x^2=4/3
x^2=4/3
In a quadratic expression, b is the linear coefficient. From the equation above, we know that b=0. Let's now calculate ( b2 )^2.
( b/2 )^2
( 0/2 )^2
Simplify

0/a=0

0^2
0
Since ( b2 )^2=0, we do not need to add anything to our equation.
x^2=4/3
x=± sqrt(4/3)
x=± sqrt(4)/sqrt(3)
x=±2/sqrt(3)
x=± 1.154700 ...
x≈ ± 1.2
Both x≈ 1.2 and x≈ - 1.2 are solutions to the equation, to the nearest tenth.