Answers:
1. There are rivets on the belts.
2. Extra information given in the problem:
a. He has 9 buckles.
b. He has 22 rivets left over.
Solution:
1. Total rivets on the belts=(12 rivets/belt)(4 belts)+(15 rivets/belt)(2 belts)
Total rivets on the belts=48 rivets+30 rivets
Total rivets on the belts=78 rivets
2. The extra information given in the problem is the information that we didn't use to solve it. In this case:
a. He has 9 buckles.
b. He has 22 rivets left over.
Answer: 
Step-by-step explanation:
1. A number written in scientific notation has the following form:

Where is
is a number between 1 and 10 but not including 10, and b is an integer.
2. The negative exponent indicates the number of places the decimal point must be moved to the left to obtain the number as a decimal number.
3. Keeping this on mind, you can know that: if the exponent of a number written in scientific notation indicates that the decimal point must be moved 5 places to the left and another number written in scientific notation indicates that the decimal point must be moved 2 places to the left, then the first number is smaller than the second one.
4. Therefore, you can arrange the numbers given in the problem as following:

9514 1404 393
Answer:
Step-by-step explanation:
1) The slope is given by the formula ...
m = (y2 -y1)/(x2 -x1)
m = (4 -(-3))/(3 -0) = 7/3
__
2) The y-intercept is the point where x=0:
(x, y) = (0, -3) . . . . . y = -3
__
3) Then the slope-intercept equation is ...
y = mx + b . . . . . . . line with slope m and y-intercept b
y = 7/3x -3