Triangle+square =54, so square =54- triangle, and then bring this formula into the first formula to get: 2 triangle = circle +2(54- triangle). From this formula, we can get two triangles = circle+108-2 triangles. After calculation, we can get four triangles = circle +6508-2 triangles. Bring "square =54- triangle" and "four triangles = circle+108" into the third formula given in the original text, and get: triangle +54- triangle+four triangles-108=86, and finally calculate triangle =35 and square =54-35.