The length of a rectangle is 3 cm more than the width. the area is 70 cm squared. find the dimensions of the rectangle

I am setting the length equal to L and the width equal to L - 3.  We can do this because we know the width is equal to 3 cm less than the length.  Because the area of a rectangle is equal to length times width, we can set up this equation:

L * (L - 3) = 70

Now, we can solve for L.  We start by distributing the L.



Next, we subtract 70 from both sides.



Now, we can factor this equation.  It becomes:



The zeros of this equation are:

L = 10, -7

Since the rectangle can't have a width of -7, we use positive 7 instead.  So, the dimensions of this rectangle are 10 cm X 7 cm

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