" <span>Substitution method can be applied in four steps.Solve one of the equations for either x = or y = .Substitute the solution from step 1 into the other equation.Solve this new equation.Solve for the second variable. ...<span>Step 1: Solve one of the equations for either x = or y = . - Google.</span></span>
I have to assume that you mean it is a similar rectangle, since a triangle can not be similar to a rectangle. In that case the original measurements are 4x4.5.
By doubling them, you get a rectangle with the measurements of 8x9 and thus the area is 72