Lets split the box in pieces and then add:
top = 20*15 = 300
sidesA = 2*20*9 = 360, is multiplied by 2 cause there are 2 sides like this
sidesB = 2*9*15 = 270, is multiplied by 2 cause there are 2 sides like this
so in total we have:
total = 300 + 360 + 270 = 930 cm^2
if we express this quantity in mm^2 we have:
<span>1cm² = 100 mm²</span>total = 930*100 = 93000 mm^2
so if the tiles are 5 mm^2 we need:
total tiles = <span>93000/5 = 18600
we need 18600 tiles of 5 mm^2</span>
Perimeter is 2l+2w in the case of a rectangle, so you would write:
2(4x - 4.25) + 2(7x +7)
U can easily put this through a calculator, but it’s 24 :)
Answer:
x = 3
Step-by-step explanation:
Given
- 3x + 2 = - 7 ( subtract 2 from both sides )
- 3x = - 9 ( divide both sides by - 3 )
x = 3
