Assume that
a and b = the two legs of the right triangle.
c = the hypotenuse.
The area of the right triangle is 750 yd², therefore
(1/2)*a*b = 750
ab = 1500 (1)
The perimeter is 150yd, therefore
a + b + c = 150 (2)
Let the side fenced with wood be a, at $5/yd. Sides b and c are fenced with steel at $10/y. The total cost is $1200, therefore
5a + 10b + 10c = 1200
or
a + 2b + 2c = 240 (3)
From (2), obtain
c = 150 - a - b (4)
Substitute (4) into (3)
a + 2b + 2(150 - a - b) = 240
-a + 300 = 240
a = 60
From (1), obtain
60b = 1500
b = 25
From (4), obtain
c = 150 - 60 - 25 = 65
Answer:
A. The length of the leg fenced with wood is 60 yd.
B. The length of the leg fenced with steel is 25 yd.
Hello,
If you are starting with the angle of 40 degrees, you have an adjacent side and hypotenuse. Therefore, it is a cosine relationship.
We can write:
cos(40) = adj / hyp
cos(40) = x / 220
To solve for x, simply multiply 220 by the cos(40).
You can write it as: 220 cos(40)
Good luck,
MrEQ
The formula for the area of a square is the side squared, or multiplied together.
Basically, if the side length is x, the area is x*x or x^2.
We can use that to set up an equation.
x^2=121
x=square root of 121=11
Hope this helps!
Short Answer: 18 minutes
Remark
The answer to this problem is less than the smallest time of the two people working together. that fact lets out C and D (38 minutes and 75 minutes). Now you have to choose 15 minutes and 18 minutes. There's a method. No guessing needed.
Givens
Let the time for Sophie = S
Let the time for Simon = M
Let the job to completion = 1
S = 45 minutes
M = 30 minutes
Step One
Convert minutes to hours.
45 minutes = 45 / 60 = 3/4 hour = 0.75 hour
30 minutes = 30 / 60 = 1/2 hour = 0.50 hour
Step Two
Set up the Equation
The formula is a form of job / hour.
Let the time = t that they both have to work
job = 1 in these problems.
1/S + 1/M = 1/t
1/0.75 + 1/0.5 = 1/t
Solve
1 ÷ 0.75 = 1.33333
1 ÷ 0.5 = 2
1.3333 + 2 = 3.33333
3.3333 = 1 / t Multlply both sides by t
3.3333*t = 1
t = 1 / 3.333333333
t = 0.3 of an hour
1 hour = 60 minutes
0.3 hours = x Cross Multiply
x = 60 * 0.3
x = 18 minutes
Answer working together it took them 18 minutes <<<<<
