Theres not much work to show
art supplies price = p 60% = .60
just multiply p * .60 = price with sale
Let the speed of river be x km/hr down stream.
Time = Distance / speed
Since river flows downstream, speed of boat down stream = Speed of boat + speed of river = (15 + x).
Since river flows downstream, speed of boat upstream = Speed of boat - speed of river = (15 - x).
Time Upstream - Time Downstream = 75 minutes
Time Upstream = 45 / (15 - x)
Time Downstream = 45 / (15 + x)
75 minutes = 75/60 = 5/4 hours
Time Upstream - Time Downstream = 75 minutes = 5/4 hours
45 / (15 - x) - 45 / (15 + x) = 5/4 Divide both sides by 45
1 / (15 - x) - 1 / (15 + x) = (5/4)*(1/45)
1 / (15 - x) - 1 / (15 + x) = 1/36
((15 + x) - (15 -x)) / (15-x)(15+x) = 1/36
(15 +x - 15 +x) / (15-x)(15+x) = 1/36
2x / (15-x)(15+x) = 1/36
(15-x)(15+x) = 2x*36
(15-x)(15+x) = 72x
225 - x² = 72x
0 = x² + 72x -225
x² + 72x -225 = 0 This is a
quadratic function, use a calculator that can solve the function, by
inputting the function.
x = 3, or -75. Since we are solving for speed, we can not have negative values.
x = 3 is the only valid solution.
Speed of the river = 3 km/hr downstream.
Copyright.
Answer:
-2
Step-by-step explanation:
So to find slope you just subtract y^1 - y^2 and divide it by x^1 - x^2
The first point is (2, 1)
The second is (0, 5)
1 is our y^1 and 5 is our y^2
1 - 5 = -4
2 is our x^1 and 0 is our x^2
2 - 0 = 2
So our slope is -4/2, reduced its -2
I hope this helped, please mark Brainliest, thank you!
Answer:y+2.9=11, 2y+1=17.2, 28.4-y=20.3
Step-by-step explanation:
Hello :
let : y the length and : x <span>the width
y = 2x +3.....(1)
xy = 77 .....(2)
by (1) subsct : y i n (2)
x(2x+3) = 77
2x²+3x -77 = 0
the descrimnent : b²-4ac ... a =2 b= 3 c = -77
3²-4(2)(-77) = 625 = 25²
x1 = (-3-25)/4 negatif refused
x2 = (-3+25)/4 =22/4 = 11/2
x= 5.5
y = 2(5.5) +3 =14</span>
