<span>B. 3/7, 18/42
This work, because you multiply 6 top and bottom
hope this helps</span>
Answer:
D. (-x+5)^2/9+(y-4)^2/4=1 (I assume there was a mistype)
Step-by-step explanation:
The first step is isolating the sine and cosine functions.
x=5-3cos(t)
x + 3cos(t) = 5
3cos(t) = 5 - x
cos(t) = (5 - x)/3
y=4+2sin(t)
y - 4 = 2sin(t)
(y - 4)/2 = sin(t)
Then, square at both sides of the equal sign
cos²(t) = (5 - x)²/3² = (5 - x)²/9
sin²(t) = (y - 4)²/2² = (y - 4)²/4
Recall the trigonometric identity and replace.
cos²(t) + sin²(t) = 1
(5 - x)²/9 + (y - 4)²/4 = 1
Given:
t1 = 3.6 h
t2 = 4.5 h
x = speed of boat
y = speed of water
Required:
a) Expression of distance traveled with moving water with 3.6h
Expression of distance traveled with moving water with 4.5h
b) Solve for y
c) Percent of boat's speed is the water current
Solution:
Working formula: distance = velocity*time
a) For travelling downstream, we get the equation
d = (x +y)*3.6
For travelling upstream, we get the equation
d = (x-y)*4.5
b) Setting the distance as equal for travelling upstream or downstream, we arrive at the equation of
(x+y)*3.6 = (x-y)*4.5
3.6x + 3.6y = 4.5x - 4.5y
8.1y =0.9x
y = x/9
c) percentage = 1/9*100% = 11.1%
<em>ANSWERS: a) d = (x+y)*36; d = (x-y)*4.5
</em> <em>b) y = x/9
</em> <em>c) 11.1%</em>
Answer:
15 percent of 90 hours = 13.5 hours
What is 15% of 90?
Y is 15% of 90
Equation: Y = P% * X
Solving our equation for Y
Y = P% * X
Y = 15% * 90
Converting percent to decimal:
p = 15%/100 = 0.15
Y = 0.15 * 90
Y = 13.5
The answer would be D
multiply -2 and (-4m-8) to get 8m+16
then subtract -2m to get 6m+16
