# Science:Math Exam Resources/Courses/MATH100/December 2016/Question 11 (a)

MATH100 December 2016
Other MATH100 Exams

### Question 11 (a)

$A$ and $B$ , two people of identical height $h$ , stand beneath a street lamp of height $L$ . $A$ walks in a straight line and at a constant speed away from the street lamp. One second later, $B$ walks in a straight line and at the same speed, but in the opposite direction, away from the street lamp. As $A$ and $B$ move away from the lamp, their shadows grow longer.

(a) Let $a$ be the length of $A$ ’s shadow, and $b$ be the length of $B$ ’s shadow. Let $x$ be the distance $A$ has walked, and $y$ be the distance $B$ has walked. Draw and label a picture that illustrates the scenario two seconds after $A$ begins to walk away from the street lamp. Your picture should indicate all relevant lengths and the associated variables.

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