Answer:
x²+49+14x.
Explanation: We know that (x+7)² will form a quadratic expression and it will have two roots that will satisfy it. We can obtain an expression by solving (x+7)². Using the property of algebraic expressions, we know that (a+b)²=a²+b²+2ab. The product obtained on multiplying (x+7)(x+7) is x²+49+14x