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5 votes
PLEASE HELP QUICK, I NEED IT

Solve for t.

d=−16t2+12t





t=38±9−4d√8

t=−12±9−4d√8

t=12±9−4d√2

t=38±49−4d−−−−−√

2 Answers

5 votes

Here are a bunch of CORRECT answers. Your answer is in the last pic. I got number 3 wrong, but it still showed the correct answer.

PLEASE HELP QUICK, I NEED IT Solve for t. d=−16t2+12t t=38±9−4d√8 t=−12±9−4d√8 t=12±9−4d-example-1
PLEASE HELP QUICK, I NEED IT Solve for t. d=−16t2+12t t=38±9−4d√8 t=−12±9−4d√8 t=12±9−4d-example-2
PLEASE HELP QUICK, I NEED IT Solve for t. d=−16t2+12t t=38±9−4d√8 t=−12±9−4d√8 t=12±9−4d-example-3
PLEASE HELP QUICK, I NEED IT Solve for t. d=−16t2+12t t=38±9−4d√8 t=−12±9−4d√8 t=12±9−4d-example-4
PLEASE HELP QUICK, I NEED IT Solve for t. d=−16t2+12t t=38±9−4d√8 t=−12±9−4d√8 t=12±9−4d-example-5
User Rockstart
by
8.0k points
3 votes
We take the equation d = -16t^2+12t and subtract d from both sides to get
0 = -16t^2+12t - d
We apply the quadratic formula to solve for t. With a = -16, b = 12, c = -d, we have
t = [ -(12)
± √( 12^2 - 4(-16)(-d) ) ] / [2 * -16]
= [- 12 ± √(144-64d) ] / (-32)
= [- 12 ± √16(9-4d)] / (-32)
= [- 12 ± 4√(9-4d)] / (-32)
= 3/8 ±√(9-4d) / 8
The answer to your question is t = 3/8 ±√(9-4d) / 8
User Cammace
by
8.3k points