2. 2x + y = -4
5x + 3y = -6

x=15/4,y=-8.25

Step-by-step explanation:

Well to begin with it make both y's equal so multiply the first equation by 3 making it into: 6.6x+3y=-12. next subtract this new equation by the other one making it one equation as, 1.6x=-6, simplify to get: x=15/4, or 3.75 input that into one of the equations the secound one would be easier to make it 18.75+3y=-6 simplify again, 3y=-24.75 than you get y as y=-8.25

∠acb = 8°

step-by-step explanation:

∠xba lies on the circle and is half the measure of the intercepted arc ax

hence

measure of arc ax = 2 × 42° = 84°

∠acb is outside the circle and is

∠acb = (arcab - arcax ), hence

∠acb = 0.5 (100 - 84) = 0.5 × 16° = 8°