the perimeter is the distance around the rectangle.
the formula for that is P = 2l + 2w
so you have 25cm = 2l + 2w, y is the length so it will be 25cm = 2y + 2w
can be rewritten as 25 = 2(y + width)
divide both sides by 2, it becomes 12.5 = y + width
solve for width by subtracting y from both sides, so you get width = y-12.5cm
part b is tricky
the formula to find the length of a side is l= (P/4)+(1/4)*squareroot(P^2-16A)
A=25, P=38 so (25/4)+(1/4)* Sqrt(25^2-16(38)) = 7.28cm
then to find length of other side use basically same formula except subtract
l= (P/4)-(1/4)*squareroot(P^2-16A) = 5.22cm
now you know the length and width of the triangle 7.28 x 5.22
so now use 7.28 as x so 2(7.28)^2-25(7.28)+76 = 0 ( this is true )
Part C solve the equation by factoring and you should get the lengths of the sides from part b
