Answer:
slope = 15
Explanation:
substitute x = - 3 and x = - 5 into f(x)
f(- 3) = - 2(- 3)² - (- 3) + 5
= - 2(9) + 3 + 5
= - 18 + 8
= - 10
then ( - 3, - 10) is one end of the secant
f(- 5) = - 2(- 5)² - (- 5) + 5
= - 2(25) + 5 + 5
= - 50 + 10
= - 40
then (- 5, - 40) is the other end of the secant
to find the slope m use the slope formula
m =
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with (x₁, y₁ ) = (- 3, - 10 ) and (x₂, y₂ ) = (- 5, - 40 )
m =
=
=
= 15