The value of y is 6 unit
The perimeter of a rectangle is given by the formula:
P=2L+2W
In this case, the length (L) is given by 3y+3 and the width (W) is given by 4y.
The perimeter (P) is given as 90 units. So, we can set up the equation:
90=2(3y+3)+2(4y)
Now, let's simplify and solve for y:
90=6y+6+8y
Combine like terms:
90=14y+6
Subtract 6 from both sides:
84=14y
Divide by 14:
y=6
So, the value of y is 6 unit