Hello,
dy=cos(x²)*2x *dx
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Use Cymath to find your answer
Answer:
the number is 15
Step-by-step explanation:
Fists we are going to sketch our cardboard sheet; since the length and the width are equal, we know that our figure will be a square in which each side will be 6 foot long. Now, we need to cut an equal size square form each corner, but we don't now how long the lengths of the square will be, so we are going to assign the variable

to each sides of our square as you can see in the picture.
<h2>
The required "option B) xy = 12" is correct.</h2>
Step-by-step explanation:
Check the options:
A) 4x = 12
Dividing both sides by 4, we get
⇒ x = 3
4x = 12 is a linear equation in one variable x.
B) xy = 12
xy = 12 is a non-linear equation.
D) 3x - 6y = 12
Dividing both sides by 3, we get
⇒ x - 2y = 4
3x - 6y = 12 is a linear equation in two variables x and y.
Thus, the required "option B) xy = 12" is correct.