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For questions 2 and 4 calculate the perimeter and 4 questions 6/8 and 10 calculate the area

For questions 2 and 4 calculate the perimeter and 4 questions 6/8 and 10 calculate-example-1

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3 votes

Answer:

Part 2)
P=2[√(20)+√(45)]\ units or
P=22.36\ units

Part 4)
P=[19+√(17)]\ units or
P=23.12\ units

Part 6)
A=36\ units^(2)

Part 8)
A=16\ units^(2)

Part 10)
A=6.05\ units^(2)

Step-by-step explanation:

we know that

The formula to calculate the distance between two points is equal to


d=\sqrt{(y2-y1)^(2)+(x2-x1)^(2)}

Part 2) we have the rectangle ABCD


A(-4,-4),B(-2,0),C(4,-3),D(2,-7)

Remember that in a rectangle opposite sides are congruent

step 1

Find the distance AB


A(-4,-4),B(-2,0)

substitute in the formula


AB=\sqrt{(0+4)^(2)+(-2+4)^(2)}


AB=\sqrt{(4)^(2)+(2)^(2)}


AB=√(20)\ units

step 2

Find the distance BC


B(-2,0),C(4,-3)

substitute in the formula


BC=\sqrt{(-3-0)^(2)+(4+2)^(2)}


BC=\sqrt{(-3)^(2)+(6)^(2)}


BC=√(45)\ units

step 3

Find the perimeter

The perimeter is equal to


P=2[AB+BC]

substitute


P=2[√(20)+√(45)]\ units

or


P=22.36\ units

Part 4) we have the quadrilateral ABCD


A(-2,-3),B(1,1),C(7,1),D(6,-3)

step 1

Find the distance AB


A(-2,-3),B(1,1)

substitute in the formula


AB=\sqrt{(1+3)^(2)+(1+2)^(2)}


AB=\sqrt{(4)^(2)+(3)^(2)}


AB=5\ units

step 2

Find the distance BC


B(1,1),C(7,1)

substitute in the formula


BC=\sqrt{(1-1)^(2)+(7-1)^(2)}


BC=\sqrt{(0)^(2)+(6)^(2)}


BC=6\ units

step 3

Find the distance CD


C(7,1),D(6,-3)

substitute in the formula


CD=\sqrt{(-3-1)^(2)+(6-7)^(2)}


CD=\sqrt{(-4)^(2)+(-1)^(2)}


CD=√(17)\ units

step 4

Find the distance AD


A(-2,-3),D(6,-3)

substitute in the formula


AD=\sqrt{(-3+3)^(2)+(6+2)^(2)}


AD=\sqrt{(0)^(2)+(8)^(2)}


AD=8\ units

step 5

Find the perimeter

The perimeter is equal to


P=AB+BC+CD+AD

substitute


P=[5+6+√(17)+8]\ units


P=[19+√(17)]\ units

or


P=23.12\ units

Part 6) Calculate the area of rectangle ABCD


A(-1,5),B(3,5),C(3,-4),D(-1,-4)

Remember that in a rectangle opposite sides are congruent

step 1

Find the distance AB


A(-1,5),B(3,5)

substitute in the formula


AB=\sqrt{(5-5)^(2)+(3+1)^(2)}


AB=\sqrt{(0)^(2)+(4)^(2)}


AB=4\ units

step 2

Find the distance BC


B(3,5),C(3,-4)

substitute in the formula


BC=\sqrt{(-4-5)^(2)+(3-3)^(2)}


BC=\sqrt{(-9)^(2)+(0)^(2)}


BC=9\ units

step 3

Find the area

The area is equal to


A=[AB*BC]

substitute


A=[4*9]=36\ units^(2)

Part 8) Calculate the area of right triangle ABC


A(-3,3),B(-3,-1),C(5,-1)

step 1

Find the distance AB


A(-3,3),B(-3,-1)

substitute in the formula


AB=\sqrt{(-1-3)^(2)+(-3+3)^(2)}


AB=\sqrt{(-4)^(2)+(0)^(2)}


AB=4\ units

step 2

Find the distance BC


B(-3,-1),C(5,-1)

substitute in the formula


BC=\sqrt{(-1+1)^(2)+(5+3)^(2)}


BC=\sqrt{(0)^(2)+(8)^(2)}


BC=8\ units

step 3

Find the distance AC


A(-3,3),C(5,-1)

substitute in the formula


AC=\sqrt{(-1-3)^(2)+(5+3)^(2)}


AC=\sqrt{(-4)^(2)+(8)^(2)}


AC=√(80)\ units -----> is the hypotenuse

step 4

Find the area

The area is equal to


A=(1/2)AB*BC

substitute


A=(1/2)(4*8)=16\ units^(2)

Part 10) Calculate the area of triangle ABC


A(3,0),B(1,8),C(2,10)

step 1

Find the distance AB


A(3,0),B(1,8)

substitute in the formula


AB=\sqrt{(8-0)^(2)+(1-3)^(2)}


AB=\sqrt{(8)^(2)+(-2)^(2)}


AB=√(68)\ units

step 2

Find the distance BC


B(1,8),C(2,10)

substitute in the formula


BC=\sqrt{(10-8)^(2)+(2-1)^(2)}


BC=\sqrt{(2)^(2)+(1)^(2)}


BC=√(5)\ units

step 3

Find the distance AC


A(3,0),C(2,10)

substitute in the formula


AC=\sqrt{(10-0)^(2)+(2-3)^(2)}


AC=\sqrt{(10)^(2)+(-1)^(2)}


AC=√(101)\ units

step 4

we know that

Heron's Formula is a method for calculating the area of a triangle when you know the lengths of all three sides.

Let

a,b,c be the lengths of the sides of a triangle.

The area is given by:


A=√(p(p-a)(p-b)(p-c))

where

p is half the perimeter

p=
(a+b+c)/(2)

we have


a=AB=√(68)=8.25\ units


b=BC=√(5)=2.24\ units


c=AC=√(101)=10.05\ units

p=
(8.25+2.24+10.05)/(2)=10.27\ units

Find the area


A=√(10.27*(10.27-8.25)(10.27-2.24)(10.27-10.05))


A=√(10.27*(2.02)(8.03)(0.22))


A=6.05\ units^(2)

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