Step-by-step explanation:
If x is the volume of the first tank, and y is the volume of the second tank, then:
x + y = 55
x = 2y + 4
Solve the system of equations using either substitution or elimination. Using substitution:
2y + 4 + y = 55
3y + 4 = 55
3y = 51
y = 17
Solve for x using either equation.
x + 17 = 55
x = 38
The first tank holds 38 gallons, and the second tank holds 17 gallons.
Answer:
The area of the cube is 486 inches^2
Step-by-step explanation:
In this question, we are tasked with calculating the area of cube with side 9 inch.
Mathematically, the area can be calculated using the formula A = 6s^2
Now, what we need to do is to substitute 9 inches for s
Thus, A = 6 * 9^2
A = 6 * 81
A = 486 inches^2
Answer:
$12
Step-by-step explanation:
assuming that the cost of delivery is constant irrespective of the number ordered
Let the cost of sandwich be x
First office
$33=4x+c where c is the cost of delivery
Second office
$61=8x+c
These two are simultaneous equation. Subtracting the equation of first office from the second office we obtain
4x=28
Therefore, x=28/4=7
The cost of delivery is 33-(4*7)=33-28=5
Therefore, one sandwich plus delivery costs 7+5=$12
Notation
The inverse of the function f is denoted by f -1 (if your browser doesn't support superscripts, that is looks like f with an exponent of -1) and is pronounced "f inverse". Although the inverse of a function looks like you're raising the function to the -1 power, it isn't. The inverse of a function does not mean the reciprocal of a function.
Inverses
A function normally tells you what y is if you know what x is. The inverse of a function will tell you what x had to be to get that value of y.
A function f -1 is the inverse of f if
<span><span>for every x in the domain of f, f<span> -1</span>[f(x)] = x, and</span><span>for every x in the domain of f<span> -1</span>, f[f<span> -1</span>(x)] = x</span></span>
The domain of f is the range of f -1 and the range of f is the domain of f<span> -1</span>.
Graph of the Inverse Function
The inverse of a function differs from the function in that all the x-coordinates and y-coordinates have been switched. That is, if (4,6) is a point on the graph of the function, then (6,4) is a point on the graph of the inverse function.
Points on the identity function (y=x) will remain on the identity function when switched. All other points will have their coordinates switched and move locations.
The graph of a function and its inverse are mirror images of each other. They are reflected about the identity function y=x.