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10 votes
10 votes
A rectangle has a width of 1/5 and a length of 10x-15

Write the perimeter of this rectangle in simple form

Write the expression that represents the are of the rectangle

and

What would be the perimeter if x=10 Show your work and circle your final answer

They have three different section so answer each section

User Doug Kaye
by
2.6k points

2 Answers

21 votes
21 votes

Answer:

1.)-29 3/5 + 20x 2.)2x-15 3.)85 1/5

Explanation:

you have 4 sides of a rectangle and to solve for the perimeter of a rectangle you have to add up all four sides. you have the width of the rectangle and the length. SO add them up once then multiply it by two.

If your trying to find the area you multiply L*W=A^2 so just multiply your length and width.

If the x was 10 just plug in you x and solve.

It gets tricky with the variable x and I'm guessing that's where you getting caught up.

for the first one you would have 1/5 + 10x - 15 then you want to multiply it by two getting -29 3/5 + 20x that's the equation you'd use for the first expression. for the second one you want to find the area so 1/5 * 10x-15 you'd then want to simplify it which would be 2x-15

and for the third one. You have the length and the width so the perimeter is calculated by (1/5 + 10(10)-15)2 1/5+100-15 and you get 85 1/5

Sorry if this is wrong.

User Manishh
by
2.7k points
24 votes
24 votes

Answer:

Explanation:

Perimeter:

Perimeter = 2*(length +width}


=2*(10x-15+(1)/(5))\\\\\\=2*(10x - (15*5)/(1*5)+(1)/(5))\\\\\\=2*(10x -(75)/(5)+(1)/(5))\\\\\\=2*(10x -(74)/(5))\\\\= 20x - (148)/(5)

Area:

Area = length * width


= (1)/(5)*(10x-15)\\\\\\=(1)/(5)*10x - (1)/(5)*15\\\\\\=2x - 3

x = 10

Perimeter = 20*10 - (148/5)


=200- (148)/(5)\\\\= (200*5)/(1*5)-(148)/(5)\\\\=(1000-148)/(5)\\\\=(852)/(5)\\\\=170.4

User Petr Gladkikh
by
2.6k points