t^2 - 10t + 24 = 0
t^2 - 10t = -24
Take half of the coefficient of t and square it.
-10t `=>` -10 `=>` -5 `=>` 25
Add this number to both sides.
t^2 - 10t + 25 = -24 + 25
t^2 - 10t + 25 = 1
Factor the polynomial using the Perfect Square Pattern.
(t - 5)^2 = 1
Square root both sides.
t - 5 = `+-` 1
t = 6
t = 4
You can check this by graphing and finding the x-intercepts.
Notice that the x-intercepts of the parabola are 4 and 6.
See the attached email for more examples of completing the square.
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First, we move the 24 to the other side:
t^2 - 10t + 24 = 0
This is in standard form: Ax^2 + Bx + C = 0, where A = 1, B = 10, and C = 24.
Subtract 24 from both sides.
t^2 - 10t = -24
Now we find half of B and square it. That is what we add to both sides. Half of -10 is -5 and (-5)^2 is 25. So we will add 25 to both sides:
t^2 - 10t +25 = -24 + 25
Now we factor the first side.
(t-5)(t - 5) = 1
(t - 5)^2 = 1
t - 5 = 1 or t - 5 = -1
t = 6 or t = 4
The solution set is t = {-4, 6}.
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