Look at the cuboid of the figure.
Its surface area is 122 cm².
What is the width of the cuboid?
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Look at the cuboid of the figure.
Its surface area is 122 cm².
What is the width of the cuboid?
To solve the problem, let's recall the formula for calculating the surface area of a cube:
(width*length + height*width + height*length) *2
Let's substitute the known values into the formula, labelling the missing side X:
2*(3*7+7*X+3*X) = 122
2*(21+7x+3x) = 122
2(21+10x) = 122
Let's now expand the parentheses:
42+20x=122
Now we move terms:
20x=122-42
20x=80
Finally, simplify:
x=4
And that's the solution!
4 cm
A cuboid is shown below:
What is the surface area of the cuboid?
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