# Hard SAT Math Question 83 — Video Explanation | 1600.now

Source: https://1600.now/hard/83

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83

For the given parabola $ax^2 + bx + c$, $a$, $b$, and $c$ are all constants. The $x$-intercepts of the parabola are at $(-4,0)$ and $(k,0)$. If $f(-13) = f(15)$, what is the value of $k$?