3b+2(b-1) = 8
3b+2b-2 = 8
5b = 8+2
5b = 10
b = 2
Answer:
3306.5
Step-by-step explanation:
a = 30
a = 16
-a² + 46a -480 = 0
(-a + 30) (a -16) = 0
(-a)(a) + (-a)(-16) + 30(a) + 30(-16) = 0
-a² + 16a + 30a -480 = 0
-a² + 46a - 480 = 0
(-a + 30) = 0 ; (a - 16) = 0
-a = -30 ; a = 16
a = 30
To check:
a = 30
-(30)² + 46(30) - 480 = 0
-900 + 1380 - 480 = 0
480 - 480 = 0
0 = 0
a = 16
-(16)² + 46(16) - 480 = 0
-256 + 736 - 480 = 0
480 - 480 = 0
0 = 0
Answer:
3 percent
Step-by-step explanation:
convert to seconds
960 seconds to 930 seconds
30 seconds ÷ 960=3 per cent