Answer:
7.5mi
Step-by-step explanation:
B. 3 √3
The shortcuts for a 30 60 90 triangle is that the:
Hypotenuse is 2 times the short leg
The long leg is √3 times the short leg.
Making it 3 √3
Another way is by the Pythagorean Theorem.
a^2+b^2=c^2
3^2+b^2=6^2
9+b^2=36
Subtract 9 from both sides
b^2=27
Square root both sides
b=5.2 or the √27
√27 can be simplified more
An equation that equals to 27 that has a perfect square is 9*3
√9* √3
The perfect square of 9 equals to 3
So 3 √3
Answer:
x = 2 cm
y = 2 cm
A(max) = 4 cm²
Step-by-step explanation: See Annex
The right isosceles triangle has two 45° angles and the right angle.
tan 45° = 1 = x / 4 - y or x = 4 - y y = 4 - x
A(r) = x* y
Area of the rectangle as a function of x
A(x) = x * ( 4 - x ) A(x) = 4*x - x²
Tacking derivatives on both sides of the equation:
A´(x) = 4 - 2*x A´(x) = 0 4 - 2*x = 0
2*x = 4
x = 2 cm
And y = 4 - 2 = 2 cm
The rectangle of maximum area result to be a square of side 2 cm
A(max) = 2*2 = 4 cm²
To find out if A(x) has a maximum in the point x = 2
We get the second derivative
A´´(x) = -2 A´´(x) < 0 then A(x) has a maximum at x = 2