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
9514 1404 393
Answer:
A
Step-by-step explanation:
You can use x=0 and x=1 to find points that must be on the graph.
f(0) = 16·0.5^0 = 16
f(1) = 16·0.5^1 = 8
Only graph A matches these points.
In the ratio, the numbers are 2 for the shortest side, 3 for the middle sized side, and 4 for the longest side.
2 is to 6 cm as 4 is to x
2/6 = 4/x
2x = 4 * 6
2x = 24
x = 12
Answer: The longest side measures 12 cm.
The length is: 42 inches
The width is : 21 inches