Answer:
18 L
Step-by-step explanation:
Given : she must mix a solution of 67% herbicide with a solution of 46% herbicide to form 42 liters of a 55% solution.
To Find: How much of the 67% solution must she use?
Let x = amount of 67% solution needed
Then 42-x=amount of 46% solution needed
Now we know that the pure herbicide in the 67% solution
So, pure herbicide = (0.67x)
The amount of pure herbicide in the 46% solution (0.46(42-x))
Now 42 liters of a 55% solution = (0.46(42-x))
So,
Amount of 67% solution + Amount of 46% solution = 42 liters of a 55% solution
⇒0.67x+0.46(42-x)=0.55*42
⇒0.67x+19.32-0.46x=23.1
⇒0.21x=3.78
⇒
⇒x = 18 liters
Hence she use 18 liters of the 67% solution
Answer:
±90
Step-by-step explanation:
√(-225) · √(-36) = (15i)·(6i) = 90i² = 90·(-1) = -90
_____
On the other hand, ...
... √(-225) · √(-36) = √((-225)·(-36)) = √8100 = 90
___
If you consider all the roots at each stage, the result is ±90. Since you're working with complex numbers here, it is reasonable to recognize every number has two square roots.
... √(-225) = ±15i
... √(-36) = ±6i
... √(-225) · √(-36) = (±15i)·(±6i) = ±90i² = ±90
Answer:
(9, 3 )
Step-by-step explanation:
under a reflection in the y- axis
a point (x, y ) → (- x, y ) , then
(- 9, 3 ) → (9, 3 )
Answer:
8 units by 10 units
Step-by-step explanation:
Hello!
Answer:
1) 7k+35
2) 9n−36
3) 4x+22
Step-by-step explanation:
1) 7(k+5)
1) 7k+7×5
1) 7k+35
2) 9(n-4)
2) 9n+9×−4
2) 9n−36
3) 4(x+5)+2
3) 4x+20+2
3) 4x+(20+2)
3) 4x+22
Hope this helps!
