Answer:
You will break even on the car wash when you buy 13.5 gallons. As long as you buy that or more, it is cheaper to get the car wash.
Step-by-step explanation:
In order to find this, we need to create equations for both situations. If we let x equal the amount of gallons purchased, we can model the first equation as:
f(x) = 3.35x
And the second equation as:
f(x) = 3.05x + 4.05
Then to find when they equal each other, we can set the two equations equal to each other and solve for x.
3.35x = 3.05x + 4.05
0.30x = 4.05
x = 13.5
This means once you buy 13.5 gallons, the prices will be the same. Any amount over that and the car wash will be cheaper
In general, √(y²) = |y|, since y can be positive or negative and y² would have the same value either way.
So,
1) if y > 0, then |y| = y, and
-15√(y²) = -15 |y| = -15y
2) if y < 0, then |y| = -y, and
-√(16y²) = -|4y| = -|4| |y| = -4 (-y) = 4y
We have to use the functions:
h ( x ) = 2 x + 5 and t ( x ) = 7 x - 6
Part A:
( h + t ) ( x ) = ( 2 x + 5 ) + ( 7 x - 6 ) = 9 x - 1
Part B :
( h · t ) ( x ) = ( 2 x + 5 ) · ( 7 x - 6 ) = 14 x² - 12 x + 35 x - 30 =
= 14 x² + 23 x - 30
Part C :
h [ t ( x ) ] = h ( 7 x - 6 ) = 2 · ( 7 x - 6 ) + 5 = 14 x - 12 + 5 =
= 14 x - 7
