The function f is defined by f(x)=a−2x, where a is a constant. find a, if the graph of f passes through the point (8,−21).

value of constant a is (-5).

Step-by-step explanation:

The function f is defined by f(x) = a - 2x

where a is a constant.

We have to find the value of a if the graph passes through (8, - 21)

If function passes through ( 8, -21 ) then x and y value of this point will satisfy the equation.

y = f(x) = a -2x

-21 = a -2(8)

-21 = a - 16

a = -21 + 16

 = -5

Therefore, value of constant a is (-5).

21/58.

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