Answer:
r = 152/55
Step-by-step explanation:
122 - 44r = - 30 + 11r
122 - 44r - 11r = - 30
- 44r - 11r = - 30 - 122
- 55r = - 30 - 122
- 55r = - 152
Answer:
a = 7
Step-by-step explanation:
I think, what you need to do, is first understand how to find the mean of anything: It's quite simple, actually, just add up all the numbers, then divide that number by the number of numbers. So, let's put it in perspective:
10, 3, 4, a, 6, 9, 10
7 is the mean. 7 is the number of numbers.
If, to find the mean is: 10 + 3 + 4 + a + 6 + 9 + 10= 7a ÷ 7, then: 10 +3 + 4+ 6 + 9 +10= 42
42 plus what divided by 7 is the question now.
42 + a ÷ 7= 7
So, 7 times 7, that's 49 minus 42 and you've got your answer: 7
Answer:
2/4
Step-by-step explanation:
Formula for the area of a circle is,
pi×radius squared
example,
radius of a circle is 2cm what's the area?use 3.14 as pi
2squared×pi
=2squared×3.14
=12.56cm squared..
hope this helps.....
Answer:
8.5
Step-by-step explanation:
First we need to get BC using the pythagoras theorem
BC² = AC² + AB²
BC² = 8² + 15²
BC² = 64+225
BC² = 289
BC = √289
BC = 17
DB = 1/2BC
DB = 1/2 * 17
DB = 8.5
Hence the length of DB is 8.5