What is #f(-9)# if #f(x)=-7x+8#?

1 Answer
Aug 2, 2018

#" "#
If #f(x)=-7x+8#,

#f(-9)=71#

Explanation:

#" "#
Given:

We must find #f(-9)# if #f(x)=-7x+8#

#f(x)=-7x+8#

Substitute the value #color(red)((x=-9)#

#rArr f(-9)=-7(-9)+8#

# rArr 63+8#

#rArr 71#

Hence, the answer is #color(blue)(71#