Minta tolong yg no.4 pakai cara yaa,makasii.

4. 2(a – 2) + 3 ≥ 3a – 7
2a – 4 + 3 ≥ 3a – 7
2a – 1 ≥ 3a – 7
-a ≥ -6
a ≤ 6

5. 2½a ≥ 12 – ½a
5/2a ≥ 12 – ½a (dikali 2)
5a ≥ 24 – a
6a ≥ 24
a ≥ 4