Answer:
Step-by-step explanation:
f(x) = y = 4x + 7
Solve for "x"
4x + 7 = y ⇒ x =
y -
Exchange the places "x" and "y"
(x) =
x -
or
(x) =
The 4 is in the hundreds place
Answer:
The volume of the solution with 20% acid is 27 gallons and the one with 10% acid is 18 gallons
Step-by-step explanation:
Myra needs to mix "x" gallons of the solution with 20% and "y" gallons of the solution with 10%. The volume of the final solution must be 45 gallons, therefore:
x + y = 45
The concentration of acid of the final solution is:
0.2*x + 0.1*y = 45*0.16
0.2*x + 0.1*y = 7.2
Therefore we have a system of equation:
x + y = 45
0.2*x + 0.1*y = 7.2
We need to multiply the first equation by -0.1:
-0.1*x -0.1*y = -4.5
0.2*x + 0.1*y = 7.2
We now sum both equation:
0.1*x = 2.7
x = 2.7/0.1 = 27 gallons
y = 45 - 27 = 18 gallons
Answer:
Let
y=f(x)
so
y=log9x
we know that
applying property of logarithms
y= log9x is equal to
------> equation 1
so
case 1) (-1/81, 2)
x=-1/81
y=2
substitute the value of y in the equation 1 to obtain the value of x
81 is not equal to -1/81-------> the point does not belong to the graph
case 2) (0, 1)
x=0
y=1
substitute the value of y in the equation 1 to obtain the value of x
9 is not equal to 0-------> the point does not belong to the graph
case 3) (1/9, -1)
x=1/9
y=-1
substitute the value of y in the equation 1 to obtain the value of x
1/9 is equal to 1/9-------> the point belongs to the graph
case 4) (3, 243)
x=3
y=243
substitute the value of y in the equation 1 to obtain the value of x
9^{243} is not equal to 3-------> the point does not belong to the graph
case 5) (9, 1)
x=9
y=1
substitute the value of y in the equation 1 to obtain the value of x
9 is equal to 9-------> the point belongs to the graph
case 6) (81, 2)
x=81
y=2
substitute the value of y in the equation 1 to obtain the value of x
81 is equal to 81-------> the point belongs to the graph