Okay so first u want to pull out a gcf and since the first term is negative u want to pull out that negative sign.
-5(t^2-4t-12)
Then you want to make a cb chart and that is when u divide the c value into factors that will equal the b value.
C=-12| B=-4
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-6,2 = -4 ??? <-------✅
So then u divide those with the a value and make to separate parenthesis that are multiplied together and equal to 0
(t-6)(t+2) = 0
Then you solve for t in each separate parenthesis
T=6 and t=-2
Since it's asking for when the ball hit the ground you can't have a negative number so in this case the answer would be 6
The ball reached the ground in 6 seconds.
Hope this helps!
