For A, divide total miles by the miles per gallon for each tire pressure to find the number of gallons of gas used:
At 30 psi: 23000 / 20.5 = 1121.95 gallons , round to 1121 gallons.
At 35 psi: 23000 / 21.1 = 1090 gallons.
Number of gallons saved: 1121 - 1090 = 31 gallons.
B) multiply the cost per gallon by the number of gallons saved:
31 gallons x $2.00 = $62.00 saved.
C) Multiply the gallons saved by 1 car by total number of cars:
31 gallons x 140 million cars = 4,340 million gallons ( 4 billion 340 million gallons)
Answer:
f(x) = 16*0.75^x
Step-by-step explanation:
first off let's use this coordinate (the one given) :
(0,16)
let's substitute this into the equation with x being 0 and f(x) being 16
16 = a*b^0
*anything to the power of 0 is 1*
so:
a = 16
now use the second coordinate :
(1,12)
and do the same by substituting 1 for x and 12 for f(x), we also know what 'a' is:
12 = 16*b^1
12 = 16 * b
b = 3/4
so :
f(x) = 16*0.75^x
4. y=4x-7 ---- first equation
y=2x+9 ---- second equation
substitude first equation into second equation
4x- 7 = 2x + 9
2x = 16
x = 8 --- third equation
substitude third equation into first equation
y = 4(8) - 7
y = 25
5. 8x+2y=-2 ---- second equation
y=-5x+1 ---- first equation
substitude first equation into second equation
8x + 2(-5x+1) = - 2
8x - 10x + 2 = - 2
2x = 4
x = 2 ---- third equation
substitude third equation into first equation
y = - 5(2) + 1
y = - 9
6. y+2x=-1 ---- second equation
y-3x=-16
y = 3x - 16 ---- first equation
substitude first equation into second equation
3x - 16 + 2x = - 1
5x = 15
x = 3 --- third equation
substitude third equation into first equation
y + 2(3) = - 1
y = - 7
Answer:
-1
Step-by-step explanation:
Answer:
look at photo
Step-by-step explanation:
substitute y = 0
determine the definded range
transform the expressions
multiply
swap sides
set the numerator equal to 0
solve
find the intersection
