Tolong jawab secepatnya

a.) 180' = 68' + 30' + (2x)'
180' = 98' + (2x)'
2x' = 180' - 98'
2x' = 82'
x' = 82'/2' = 41'

b.) 90' = 2x' + 3x'
90' = 5x'
x = 90'/5' = 18'

Menurut saya seperti ini. Semoga bermanfaat