I’m working on 3 and 4 only maybe if I can have some explanation so I can understand and do more of these next week.
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4.b.
Answer: See below.
Step-by-step explanation:
3.a. f(6) means use x = 6 in the equation f(x) = 2x
so f(6) would be f(6)= 2(6)
f(6) = 12
3.b. f(-11) = 2(-11)
f(-11) = -22
3.c. f(2.75) = 2(2.75)
f(2.75) = 5.5
3.d. This is turned around. We are told f(x)=20, so what would x need to be for f(x) to be 20? Since f(x) = 2x, we can say 20 = 2x. Therefore x = 10
f(10) = 20
The rest of (3) are solved in the same fasion.h
4.a. f(7) = 5(7)+50
f(7) = 85
4.b. f(-12)
f(-12) = 5*(-12)+50
f(-12) = -60
Continue in the same fashion for these types of problems.