Multiply and simplify: 3a(4a2 – 5a + 12) 7a3 – 2a2 + 15a 12a3 – 15a2 + 36a 12a2 – 15a + 36 7a2 – 2a + 15

Step-by-step explanation:

To solve this problem you must apply the procccedure shown below:

1. You have the following expression:

2. Then, you must apply the Distributive property. In other words, you need to multiply by each term inside the parentheses.

3. You need to remember the properties of exponents. When you have equal base, you only need to multiply the coefficients, write the base and add the exponents. Therefore, you have:

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

answer: 94

step-by-step explanation: 79+91+92+94+94 = 450 divided by 5 (since there are 5 number that are being added) = 90