Question 1161088
x^2-8/9x=64/81 by completing the square, what do you add to both sides of the equation?
<pre>{{{matrix(1,3, x^2 - (8/9)x, "=", 64/81)}}}
Squaring {{{matrix(1,3, 1/2, of, b)}}} and then ADDING the result to each side of the equation result in: {{{highlight_green(matrix(3,3, x^2 - (8/9)x + ((1/2) * (- 8/9))^2, "=", (64/81) + ((1/2) * (- 8/9))^2,
x^2 - (8/9)x + (- 4/9)^2, "=", (64/81) + (- 4/9)^2,
x^2 - (8/9)x + 16/81, "=", 64/81 + 16/81))}}}
Can you now see what has been added to both sides, after comparing the final equation to the given one?
P.S. IGNORE what that woman says. She doesn't have a CLUE. "b" is NOT {{{4/9}}}.
If you compare {{{system(matrix(1,3, Ax^2 + Bx + C, "=", 0), to, matrix(1,3, x^2 - (8/9)x - 64/81, "=", 0))}}}, it will be quite clear to you what coefficient "B" represents.