Inverse
replace f(x) wih y
solve for x
replace x with f⁻¹(x) and y with x
so
f(x)=3x+5/7
replace
y=3x+5/7
solve for x
minnus 5/7 both sides
y-5/7=3x
divide both sides by 3
=x
replace with f⁻¹(x)
f⁻¹(x)=
Answer:
x<12
Step-by-step explanation:
Answer:
x=2, y=13
Step-by-step explanation:
In order to get this by addition which is the easiest way for this you want to take both equations
y=3x+7 and y=-4x+21 and move x to the other side of the equation so it is like 4x+y=21 and -3x+y=7 like that now you have to get rid of one of the exponents and the easiest one to get rid of is y so I'm going to multiply -3x+y=7 by negative 1 so it becomes 3x-y=-7 that way the equations value has not changed since I multiplied both sides and now when I add
4x+y=21 and 3x-y=-7 It'll look like
4x+y=21
3x-y=-7 add those It will get rid of the y
then get 7x=14 simplify to get x=2 then you can take -3x+y=7 plug in x and get
-3(2)+y=7 multiply into -6+y=7 then simplify you get y=13
Answer:
The speed of the first train is 45 mph and the speed of the second train is 75 mph
Step-by-step explanation:
Let x represent the speed of the first train in mph. Since the second train, is 30 mph faster then the first, therefore the speed of the second train is (x + 30).
The first train leaves at 1:00 pm, therefore at 6:00 pm, the time taken is 5 hours. Therefore the distance covered by the first train at 6:00 pm = x mph * 5 hours = 5x miles
The second train leaves at 3:00 pm, therefore at 6:00 pm, the time taken is 3 hours. Therefore the distance covered by the second train at 6:00 pm = (x + 30) mph * 3 hours = (3x + 90) miles
Since the second train overtakes the first at 6:00 pm, hence:
3x + 90 = 5x
2x = 90
x = 45
Therefore the speed of the first train is 45 mph and the speed of the second train is 75 mph (45 mph + 30 mph).
Answer:
He earned $420.
Step-by-step explanation:
I hope this helps! Have a great rest of your day!
