Twice means two times something so2a. Four more than means adding for so your answer is 2a+4
How I would do it is place a point at 1 then go up 1 over 4 because of your slope 1/4. Same as for going down except down 1 over 4. Hope this helped:)
Juan’s lunch would have costed less if he paid separately. his lunch is 5.25
the bill 37.20
37.20 / 5
$7.44 each kid
7.44 - 5.25 = 2.19
$2.19 less if he paid separately
The answer to 8a. is 17, the answer to 8b. is 3.9, the answer to 8c. is 1 / 2, the answer to 8d. is 7 7 / 8, the answer to 9a. is commutative property, the answer to 9b. is multiplicative identity property, the answer to 9c. is associative property, and the answer to 9d. is additive inverse property.
Regarding the whole "explain using mental math" thing, I pretty much just used the fact that 8a. and 8b. both had the same number of decimal places. For 8c., I just made each number have a denominator of 10. And last, for 8d., all of the denominators were already the same, which made it pretty easy. I apologize for this section of my answer being so informal lol, I haven't had to do these kinds of problems in like 5 years <span />
Answer:
9/1 x 3/1
Step-by-step explanation: