Question

Quadratic polynomials $P(x)$ and $Q(x)$ have leading coefficients of $2$ and $-2,$ respectively. The graphs of both polynomials pass through the two points $(16, 54)$ and $(20, 53).$ Find $P(0) + Q(0).$

Answer

Answer: 116

Concepts:polynomial linear equation

Difficulty rating: 1890

Solution:

Let $R(x) = P(x) + Q(x).$ The leading coefficients $2$ and $-2$ cancel, so $R$ is a linear function. Since both graphs pass through $(16, 54)$ and $(20, 53),$ we get $R(16) = 108$ and $R(20) = 106.$

The slope of $R$ is $\frac{106 - 108}{20 - 16} = -\frac{1}{2},$ so $\begin{aligned} P(0) + Q(0) &= R(0) \\ &= R(16) + 16 \cdot \frac{1}{2} \\ &= 108 + 8 = 116. \end{aligned}$

2022 AIME I Problem 1

Answer: 116

Difficulty rating: 1890

Solution:

Problem 1 in Other Years