Question

practice exercises lesson 7.3b
possible points: 10
match each function with the correct value.
$f(x) = 4x - 3$ find $f(5)$
$f(x) = x^2 + 1$ find $f(3)$
$g(r) = 3r^2 + 5$ find $g(-1)$
:: 10 :: 8 :: 17

Explanation:

Step1: Solve \( f(5) \) for \( f(x) = 4x - 3 \)

Substitute \( x = 5 \) into \( f(x) \): \( f(5)=4(5)-3 \)
Calculate: \( 4\times5 = 20 \), \( 20 - 3 = 17 \)

Step2: Solve \( f(3) \) for \( f(x) = x^2 + 1 \)

Substitute \( x = 3 \) into \( f(x) \): \( f(3)=3^2 + 1 \)
Calculate: \( 3^2 = 9 \), \( 9 + 1 = 10 \)

Step3: Solve \( g(-1) \) for \( g(r) = 3r^2 + 5 \)

Substitute \( r = -1 \) into \( g(r) \): \( g(-1)=3(-1)^2 + 5 \)
Calculate: \( (-1)^2 = 1 \), \( 3\times1 = 3 \), \( 3 + 5 = 8 \)

Answer:

• \( f(x) = 4x - 3 \), \( f(5) \): \( 17 \)
• \( f(x) = x^2 + 1 \), \( f(3) \): \( 10 \)
• \( g(r) = 3r^2 + 5 \), \( g(-1) \): \( 8 \)