x^2–14x+49; 25a^2+10a+1; 100+80c+c^2; a^2–6ac+9c^2; a^4–12a^2+36; –25a^2–80ab–64b^2; x^2–12x+36; 25; 25a^2+80a+64; a^2–6b+9b^2; a^4–14a^2+49; –4m^2–36mn–81n^2;(2a+b)^2; (3a–b)^2; 9/19a^2–2ab+16/9b^2; (1/2a+b)^2; (ab+1)^2; (b–a^2)^2; (a–3b)^2; (4a+b)^2; (2/3a–3/2b)^2; (1/2a–b)^2; (1–ab)^2; (a^2+b)^2