The weight in 1980 is 
kilograms
<em><u>Solution:</u></em>
From 1980 to 1990, Lior’s weight increased by 25%
His weight is "k" kilograms in 1990
<em><u>To find: weight in 1980</u></em>
This is a percentage increase problem
Let "x" be the weight in kilograms in 1980
<em><u>The percentage increase is given by formula:</u></em>
Here,
Initial value in 1980 = x
Final value in 1990 = k
Percentage increase = 25 %
<em><u>Substituting the values in formula,</u></em>
Thus the weight in kilograms in 1980 is
Ans(a):
Given function is 
we know that any rational function is not defined when denominator is 0 so that means denominator x+4 can't be 0
so let's solve
x+4≠0 for x
x≠0-4
x≠-4
Hence at x=4, function can't have solution.
Ans(b):
We know that vertical shift occurs when we add something on the right side of function so vertical shift by 4 units means add 4 to f(x)
so we get:
g(x)=f(x)+4
We may simplify this equation but that is not compulsory.
Comparision:
Graph of g(x) will be just 4 unit upward than graph of f(x).
Ans(c):
To find value of x when g(x)=8, just plug g(x)=8 in previous equation
4x-3x=-1-16
x=-17
Hence final answer is x=-17
<u>Answer:</u>
<h2>(4, 6)</h2>
<u>Explanation:</u>
x = -4 + (12 - (-4))/2
x = -4 + (12+4)/2
x = -4 + 16/2
x = -4 + 8
x = 4
y = 2 + (10 - 2)/2
y = 2 + 8/2
y = 2 + 4
y = 6
the coordinates of the center of the circle: (4, 6)
235.24 + 45.58 = 280.82
280.82/2 = 140.41
each check was for $140.41
Independent quantity (x) is number of races won
dependent quantity f(x)...or y is total virtual money
the function is : f(x) = 500x + 5000 or y = 500x + 5000
