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
Mr. and Mrs. Bailey need to invest $2906.50 so as to send their son to college.
<h3>
Compound interest</h3>
Compound interest is given by:
where A is the amount after t years, P is initial amount, r is the rate and n is the times compounded per period
Given that n = 1, r = 9% = 0.09, A = $7500 t = 11. Hence:
Mr. and Mrs. Bailey need to invest $2906.50 so as to send their son to college.
Find out more on Compound interest at: brainly.com/question/24924853
Answer: 0
Step-by-step explanation:
So the slope of a line is equal to rise over run, or the change in x over the change in y. We can solve for the change in x and the change in y by finding their differences. For the math, we use the formulas y2 - y1/x2 - x1. Filling in this formula we get, (5-5)/(3-13), which is equal to 0/10. Because 0 divided by anything is 0, the answer here is 0.
You should use photo math it can help you instantly with math problems!
7. 65 + 75 = 140
180 - 140 = 40
( I think this is the answer)
