A blackboard has an area of 28 and a perimeter of 22 ft. What are the dimensions of the board?
2 ft by 11 ft
2 ft by 14 ft
4 ft by 7 ft
7 ft by 7 ft

the ancer is c

Step-by-step explanation:

Option (c) is correct.

Dimension of board is 4 ft by 7 ft.

Step-by-step explanation:

Given : A blackboard has an area of 28 feet squared and a perimeter of 22 ft.

We have to find the dimension of blackboard and choose the correct option from given options.

Since blackboard is in shape of rectangle thus,

Area of blackboard is 28 feet²

That is, Area of rectangle =  28 feet²

We know Area of rectangle = length × Breadth

substitute, we get,

28 = length × Breadth (1)

Also, Perimeter of blackboard is 22 feet.

That is, Perimeter of rectangle =  22 feet

We know, Perimeter of rectangle = 2 (length + Breadth)

substitute, we get,

22 = 2 (length + Breadth)  

11 = (length + breadth)   (2)

Let length be l and breadth be b

Solving (1) and (2) ,

from (2)

b = 11 - l  ..(3)

put (3)  in (1) , we get,

28 = L (11 - L)

Multiply, we get,

Solving above quadratic equation using middle term split method, we get,

Solving, e get,

Using zero product property, we get,

 and

We get ,

 and

Thus, length can be 4ft or 7 ft

Substitute, L in (3) , we get,

b = 11 - 4 = 7 ft

b = 11 - 7 = 4 ft

Thus, Dimension of board is 4 ft by 7 ft.

Option (c) is correct. hope it helped <3

answer:

it will cost 480 dollars to refurbish the larger wood floor

step-by-step explanation:

as it's a ratio of 4 that costs 384 dollars, divide the price by the ratio

384 / 4 = 96 dollars

96 dollars per unit of the ratio

now to get the price to refurbish the larger wood floor, times the price by the units

96 * 5 = 480

a line is an defined derm because it

a)contains an infinite number of points b) can be used to create other geometric shapes c)describes something that does not have width or depth d) is a term that does not have a formal definition. a line is an undefined term because it: contains an infinite number of points.