Well 2 tens are 20 and 15 ones are 15 so 2 tens and 15 ones are 35 as an answer.
Answer:
3.1*10^10
Step-by-step explanation:
31 billion would be written like that because... there are 9 0's left, and that goes up to 10 because i turned 31 to 3.1 not 31, so that value after a decimal point adds 1
Answer is in a photo. I couldn't attach it here, but I uploaded it to a file hosting. link below! Good Luck!
bit.
ly/3a8Nt8n
18.
-2(-9)+3
18+3
21
Explanation: -2(-9) When multiplying numbers that have both a negative sign, the answer is positive. Multiply normally.
19.
-6(-4)0
24(0)
0
Explanation: -6(-4) As I explained before, the answer would be positive.
24(0) Every number multiplied by 0 is 0.
20.
56+(-7)
49
Explanation: 56+(-7) Any problem like this is just basically going to be 56-7.
21.
-36+(-4)
-40
Explanation: -36+(-4) You are simply adding normally then adding the sign. This will only work if the signs are the same. (Signs are positive and negative.)