Question

Given f(x)-3x-1 and g(x)-2x-3, for which value of x does g(x)=f(2)?

Answer 1

f(2)

• 3(2)-1
• 6-1
• 5

so

• g(x)=5
• 2x-3=5
• 2x=8
• x=4

Answer 2

x = 4

Explanation:

Given functions:

`\begin{cases}f(x)=3x-1\\g(x)=2x-3\end{cases}`

f(2) means substitute x = 2 into function f(x):

`\begin{aligned}g(x) & = f(2)\\ \implies 2x-3 & = 3(2)-1\\2x-3 & = 6-1\\2x - 3 & = 5\\2x - 3 + 3 & = 5 + 3\\2x & = 8\\(2x)/(2) & = (8)/(2)\\x & = 4\end{aligned}`

Therefore, g(4) = f(2).