1)Calculate the product:
21a + 10a - 3a
2)Collect like terms:
28a
Answer:
28a
Because angleCBD+angleBDC+angleC=180
so angleCBD+angleBDC=180-angleC=180-82=98
because BC=DC
so angleCBD=angleBDC
so 2 angleCDB=98
so angleCDB=49
so y=29
by Joy Xu,紫馨雪汐
Two over four because you just multiply by two2/4
Answer:
18.3
18.3 only has three significant figures while the other numbers have more