Suppose that Tom has x quarters. Since Tom has 16 coins in all, the rest of the coins, 16 - x of them, must be nickels.
The value of x dimes is 0.25x dollars (since each quarter is 25 cents), and the value of 16 - x dimes is 0.10(16 - x) (since each dime is 10 cents). The total value of these coins, in dollars, is:
0.25x + 0.10(16 - x).
Since these coins are worth $2.50, we have the equation:
0.25x + 0.10(16 - x) = 2.50.
Solving this yields x = 6. Therefore, Tom has 6 quarters and 16-6 = 10 dimes.
A because the earnings/9 all equal the number of hours pradeep worked
Dilation and reflection
-multiplication of - =reflection
example -(x)
-multiplication of any number other than 1=dilation
example 3x
-addition/subtraction inside the function=horizontal translation
Example (x-3)
-addition/subtraction outside the function=vertical translation
Example x-3
<span>120/x - 120/(x+10) = 1
120x + 1200 - 120x = x(x+10)
1200 = x^2+10x
x^2 + 10x - 1200 = 0
(x+40)(x-30) = 0
Positive solution:
x = 30 km/hr (rate on the 1st trip)
x+10 = 40 km/hr (rate on the return trip)</span>