Inverse variation:
k is a constant
Use the given information (when x=4 y=4) to find the value of the constant:
Then, the given relationship has the next equation:
Use the equation above to find y when x=2:
Then, when x=2, y=8
Answer:
C. x < 40
Step-by-step explanation:
x/5 - 3 < 5
x/5 -3 + 3 < 5 + 3
x/5 < 8
(5/1) x/5 < 8 (5/1)
x < 40
Answer:
x = -3 and y = -4
x + y = -3-4 = -7
Step-by-step explanation:
-4x + 9y = -11 ------------------------------------------------------------------------(1)
-3x + 7y = -9--------------------------------------------------------------------------(2)
multiply through equation (1) by 3 and multiply through equation(2) by 4
-12x + 27y = -33 -----------------------------------------------------------------------(3)
-12x + 28y = -36 ----------------------------------------------------------------------(4)
subtract equation (1) from equation (2)
y = -3
substitute y = -3 into equation (2)
-3x + 7(-3) = -9
-3x -21 = -9
add 21 to both-side of the equation
-3x -21 + 21 = -9 + 21
-3x = 12
divide both-side of the equation by -3
-3x/-3 = 12/-3
x = -4
x = -3 and y = -4
Answer:
f^-1(x)=1/4x+2
Step-by-step explanation:
y=4x-8
change x and y
x=4y=8
switch sides
4y-8=x
add 8
4y=x+8
divide both sides by 4
y=1/4x+2
substitute f^-1(x) for y
f^-1(x)=1/4x+2
