it says that the width is 10mm shorter than the length. The length is L so for a) you write l-10 for the width because it says the width is 10mm shorter than L(length). B) Perimeter is 2(L+w), substitute the equations in. P=244, so 244= 2(l+l-10). distribute the 2, so it will be 2l+2l-20=244, add 20 to both sides that will lead to 2l+2l=264, add the like terms which will be 4l=264, divide 4 both sides, l=66. Length=66mm, substitute l for 66, the width will be 66-10=56. Length is 66mm, width is 56 mm
