How do you evaluate the function #f(x) =x^2- 7x + 10# and #g(x)=1-x^2 # for f(-2)?

Question

1489 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-07-02T14:02:09

See a solution process below:

Because we are evaluating #f(-2)# the information about #g(x)# is extraneous.

To evaluate #f(-2)# we need to substitute #color(red)(-2)# for every occurrence of #color(red)(x)# in #f(x)# and calculate the result:

#f(color(red)(x)) = color(red)(x)^2 - 7color(red)(x) + 10# becomes:

#f(color(red)(-2)) = (color(red)(-2))^2 - (7 * color(red)(-2)) + 10#

#f(color(red)(-2)) = 4 - (-14) + 10#

#f(color(red)(-2)) = 4 + 14 + 10#

#f(color(red)(-2)) = 28#