tolong di bantu teman-teman

f(x)=ax + b
• f(3)= 3a + b=13
•f(5)= 5a + b=25
Pakai eliminasi
5a+b=25
3a+b=13
-------------- –
2a= 12
a = 12/6
a = 2

cari B substitusi
3a+b=13
3(2)+b=13
6+b=13
b=13-6
b =7

Nilai 2a+3b= 2(2)+3(7)
= 4 + 21= 25