The diagram below shows the graph of
=
У x2
-
2x - 8.
To solve a quadratic equation graphically, a line, P, can
be added to the graph.
The solutions of the equation are
= -1 and x = 5.
a) What is the equation of the line P? Give your answer
in the form y = mx + c.
b) The equation was ax² + bx + c = 0. Find the value
of a, b and c.
9-
8-
7-
6-
4-
3-
6554 m
་་
1.
6-5-4-3-2-10 12345678 x
-2-
-3-
-4-
-5-
-8-
-10+
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