ax + by = 2020
ax – by = 2022
Jika bx = 43, maka ay =
A. -47
B. 47
C. -37
D. 37
E. -33
2. Diketahui sistem persamaan
Jawaban:
-47
Penjelasan :
- Cari a
ax+by=2020
ax-by=2022
——————-+
2ax=4042
ax=2021
a=2021/x
- Cari y
ax+by=2020
2021+by=2020
by=-1
y=-1/b
- substitusi
ay = 2021/x × -1/b
ay = -2021/bx
ay = -2021/43
ay = -47
CMIIW ^.^