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SOLVING QUADRATIC EQUATIONS
(Part 2)
PART A ~ INTRODUCTION
Steps for Representing and Solving a Problem involving a Quadratic Equation:
1.
2.
3.
4.
5.
Write a “LET” statement.
Draw and label a diagram (if applicable).
Write an equation derived from the question
(using the variable derived in the first step).
Solve the equation by factoring or using the quadratic formula.
Answer the question by writing a concluding statement.
NOTE: Any solution of an equation that does not work in the
context of a problem is said to be an inadmissable solution.
PART B ~ EXAMPLES
Example 
The sum of an integer and its square is 272. Determine the possible
value(s) of the integer.
Example 
The function, ℎ(𝑡) = −5𝑡 2 + 20𝑡 + 2, gives the approximate height, ℎ, in
metres, of a thrown football as a function of time, t, in seconds, since it
was thrown. The ball hit the ground before a receiver could attempt a
catch. Determine how long the ball’s height was at least 17m.
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Example 
Last year at the annual talent show, tickets sold for $11 and 400 people
attended. Prices will increase this year. A survey has shown that for
every $1 increase in price, attendance at the show will drop by 20 people.
Determine the selling price that would result in a revenue of $4805.
(NOTE: Revenue = Price x Quantity)
Example 
A solar blanket has a length of 3m more than its width. If the area of the
solar blanket is 28m2, determine the length of the blanket.
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Example 
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A dining room measures 5m by 4m. It will be redesigned by adding a
strip of floor of uniform width to two adjacent sides of the room.
Determine the width of the strip if the area of the new room will be 25m2.
HOMEWORK: p.178 #8–14