The exponential function is defined as y = a(1+r)^x, where "a" represents the original account and "r" the rate of growth or decay.
Then we have the following:
1) 22% grow
y = a( 1 + 22%/100 )^x = a(1.22)^x
So the solution is: 124(1.22)^x
2) 12% decay
y = a( 1 - 12%/100 )^x = a(0.88)^x
So the solution is: y = f(x) = 44(0.88)^x
3) 20% decay
y = a( 1 - 20%/100 )^x = a(0.8)^x
So the solution is: f(x) = 22(0.8)
4) 12% Groth
y = a( 1 + 12%/100 )^x = a(1.12)^x
So the solution is: f(x) = 42(1.12)^x
A. As we observe more numbers, we will always get closer to the actual average.
Please, use parentheses to enclose each fraction:
y=3/4X+5 should be written as <span>y=(3/4)X+5
Let's eliminate the fraction 3/4 by multiplying the above equation through by 4:
4[y] = 4[(3/4)x + 5]
Then 4y = 3x + 20
(no fraction here)
Let 's now solve the system
4y=3x + 20
4x-3y=-1
We are to solve this system using subtraction. To accomplish this, multiply the first equation by 3 and the second equation by 4. Here's what happens:
12y = 9x + 60 (first equation)
16x-12y = -4, or -12y = -4 - 16x (second equation)
Then we have
12y = 9x + 60
-12y =-16x - 4
If we add here, 12y-12y becomes zero and we then have 0 = -7x + 56.
Solving this for x: 7x = 56; x=8
We were given equations
</span><span>y=3/4X+5
4x-3y=-1
We can subst. x=8 into either of these eqn's to find y. Let's try the first one:
y = (3/4)(8)+5 = 6+5=11
Then x=8 and y=11.
You should check this result. Subst. x=8 and y=11 into the second given equation. Is this equation now true?</span>
Answer:
The total amount paid by Gabriel at the local gas station is $70.49.
Step-by-step explanation:
Cost of gasoline per gallon = $2.75
Cost of diesel per gallon = $3.02
Amount of gasoline Gabriel needs = 15.2 gallons
Amount of diesel Gabriel needs = 9.5 gallons
Compute the total amount paid by Gabriel at the local gas station as follows:
Total Cost = Cost of gasoline × Amount of gasoline
+ Cost of diesel × Amount of diesel

Thus, the total amount paid by Gabriel at the local gas station is $70.49.
The complete answer is 2.25E-17
but I think it may be A