Answer:
well I would love to help-where is the pic...?
Answer:
The dimensions are 9m by 18 m
Step-by-step explanation:
The perimeter will be
x+y+x for the three sides ( the wall is the fourth side)
2x+y = 36
Solving for y
y = 36-2x
The area is x*y and we want it maxed
A =x( 36-2x)
36x-2x^2
Taking the derivative
dA /dx = 36 - 2 * 2x
Setting this equal to zero to find the max
0 = 36 - 4x
4x = 36
Divide by 4
x = 36/4
x = 9
Now find y
y = 36-2x
y = 36 - 2*9
y = 36 - 18
= 18
The dimensions are 9m by 18 m
Area of rectangle = l × b
l = 70cm
b = 8cm
Area = 70 × 8 = 560cm²
Area of rectangle = l × b
l = 78cm
b = 15cm
Area = 78 × 75 = 1170cm²
Answer:
x = y = (15/2)√2
Step-by-step explanation:
You can recognize this as an isosceles right triangle, so x=y. They Pythagorean theorem then tells you that ...
15² = x² + x²
225/2 = x²
√(225/2) = x = √(225·2/4) = (15/2)√2
The solution is x = y = (15/2)√2.
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<em>Comment on isosceles right triangles</em>
It is worth remembering that the ratio of sides of an isosceles right triangle is ... side : side : hypotenuse = 1 : 1 : √2.
Knowing this lets you write down the solution to this problem as ...
x = y = 15/√2
Of course, the denominator of this fraction can be rationalized by multiplying the fraction by (√2)/(√2) to get (15√2)/2 or (15/2)√2.
The answer for your question is B. 5
