Question

Can someone help me with number 5 or 6. ( find the perimeter and area)

Answer 1

5.
`P = 11.2 cm`,
`A=7.8cm^2`

6.
`P = (4x -28) yds`,
`A= (x-7)yds^2`

Explanation:

5) Because the figure is a square then the diagonal splits the shape into two isosceles right triangles then the triangles are 45° 45° 90° triangles and the rule for such triangle is that the hypotenuse(in this case 4) is equal to a leg ·√2 so to find the leg we divide the hypotenuse by √2 so

4/√2 which is approximately 2.83 which when rounded to the nearest tenth is 2.8

so x = 2.8 cm

And because the figure is a square the perimeter is the length if a side times four so

P= 2.8(4)

P = 11.2 cm

A= 2.8(2.8)

A = 7.84cm^2 which when rounded to the nearest tenth is 7.8cm^2

6) This figure is also a square so the same rules apply for finding perimeter and area so

P = 4(x-7)

P = 4x - 28

P = (4x -28) yds

A = (x - 7)(x-7) which would just be A=(x-7)yds^2 or we could expand our answer

Use the FOIL method

x^2 -7x -7x + 49

Combine like terms

x^2 -14x +49