Set h to 640 and solve for t:
640 = -490t^2 + 1120t
Subtract 640 from both sides:
-490t^2 + 1120t - 640 = 0
The formula to solve a quadratic equation is:
x = -b -/+ sqrtroot (b^2-4ac)/(2a) where a = -490, b = 1120 and c = -640
Solve:
x = -1120 -/+ sqrtroot (1120^2-4(-490)(-640) )/ 2(-490)
x = 8/7 = 1.1428 = 1.14
Time was 1.14 seconds
Well for 3. you use the Pythagorean theorem to say that 28^2 - 18^2= x^2 so 21.4 and for 4. the Pythagorean theorem says a^2 + b^2 = c^2 with c being the hypotenuse of any right triangle so the sums of the two smaller squares make the sum of the larger square making the answer b
Answer:
0.55555
Step-by-step explanation:
the 5 keeps repeating
-6 is the slope
Hope this helps
Answer: Henry read for a total of 40 minutes
Step-by-step explanation: 3:00 - 0:50 is 2:10 then 2:10 - 1:30= 40 minutes