Answer:
The speed on motorboat is 20 mph
Step-by-step explanation:
here, we want to find the speed on the motorboat
if he has a speed of x mph on the motor boat, his speed on the ski will be (x + 10) mph
The total hours is 4 hours
Mathematically; speed = distance/time
Time on ski is 27/x+ 10
Time on motor boat is 62/x
The addition of both is 4
Thus;
27/(x + 10) + 62/x = 4
27(x) + 62(x + 10) = 4(x)(x + 10)
27x + 62x + 620 = 4(x^2 + 10x)
89x + 620 = 4x^2 + 40x
4x^2 -49x-620 = 0
using the quadratic formula;
{-b ± √(b^2-4ac)}/2a
where a = 4, b = -49 and c = -620
= 49 ± √(-49)^2-4(4)(-620)/8
So we have
49+ 111/8 or 49-111/8
Speed cannot be negative
(49 + 111)/8
= 20 mph
If my memory serves me well, the only wtatement which is true is the last one: <span>D) All linear equation and all quadratic equations are polynomial equations.</span>
False
true
false
false
Mark brainliest please
Answer:
He has 4 more to hang
Step-by-step explanation:
13 total; you must add the 5 he already hung in the morning plus, the 4 he hung in the afternoon; leaving you with 4 because 5 plus 4 is 9. 13 minus 9 is 4.
Answer:
6 : 23
Step-by-step explanation:
