A AS
Step-by-step explanation:
1)Calculate the product:
21a + 10a - 3a
2)Collect like terms:
28a
Answer:
28a
The answer is definitely B
Answer:
144
Step-by-step explanation:
Because the horizontal lines are parallel <7 is the same as <4. Because <1 and <7 are on a straight line they must add up to 180. <7 + 36 = 180 so <7=144 so <1 is also 144.