Question

Mohon dibantu ya plus caranya​

Answer 1

4x − 5y = 22.......× 3

3x + 2y = 5..........×4

12x − 15y = 66
12x + 8 y = 20
−−−−−−−−−−− −
−23y = 46

y = −2

3x + 2y = 5

3x + 2(−2) = 5

3x − 4 = 5

3x = 9

x = 3

jadi a = 3, b = −2

2a − 3b = 2(3) − 3(−2)= 6 + 6 = 12

jawaban (A)