5.
Let x be the age of the father and y be the age of the son. As of today, he's 3 times older, so we have 
10 years ago their ages were, respectively, x-10 and y-10, and the father was 5 times older: 
So, we have the system
Using the first equation, we can substitute every occurrence of "x" with "3y" in the second equation:
So, the son is 20 years old, which means that the father is 60 years old.
Indeed, 10 years ago they were 10 and 50 years old, so the father was 5 times older.
6.
Let x be the age of the grandfather and y the age of the granddaughter. We know that the grandfather is 10 times older: 
He also is 54 years older: 
Again, if we substitute x=10y in the second equation we have
Answer:
168 adult tickets
Step-by-step explanation:
3.75(82) (82 students)
307.5
2071.5 - 307.5 ( you subtract since you only need to know the number of adults)
1764
1764/10.5 (you divide since each adult is 10.5$)
168
Answer:
a = 12
Step-by-step explanation:
Formula for calculating the slope of a line is expressed as;
m = ∆y/∆x
m = y2-y1/x2-x1
Given
m = 1/2
x1 = a
y1 = 14
x2 = 8
y2 = a
Required.
Value of a
Substitute the given parameters into the formula
1/2 = a-14/8-a
Cross multiply
1(8-a) = 2(a-14)
8-a = 2a-28
Collect like terms
-a-2a = -28-8
-3a = -36
a = -36/-3
a = 12
Hence the value of a is 12
<span>So the question is 25% of what number is 21. Lets turn that into an equation: let x be the number we are looking for. We need to take 25% from it and we know that that is equal to 21. Mathematically: 25% * x= 21. Or: (25/100) * x = 21. When we multiply both sides with 100 and divide both sides by 25 we get: x=21*(100/25). And we get that x=84. </span>
Answer:
1/2
Step-by-step explanation:
When you analyze the graph for your slope, you RISE over RUN meaning you go up/down first and then left/right next.
I got 1/2 because RISE over RUN is written the same (or is the same) as Y over X
2/4 = 1/2
3/6 = 1/2
4/8 = 1/2
5/10 = 1/2
therefore your slop must be 1/2!
hope this helpsss
