Answer:
a = -2
b = 7
Step-by-step explanation:
5a+3b=11
-2a+3=b
substitute for b:
5a + 3(-2a + 3) = 11
5a -6a + 9 = 11
-a = 2
128
32/0.25=128
Right angles is 90° so 90°+30°=120°.A straight line is 180°. So you do 180°-120° which is 60. So A=60°