Answer:

Step-by-step explanation:

[Divide both sides by
]
[Square both sides]
[Multiply both sides by m]
[Bring n to the right]
[Square root both sides]
Answer:
The value of x is
.
Step-by-step explanation:
Given expression is:

We have to solve this for x.
First we will multiply both sides of the equation by 3

2(x-2) = 12x
2x-4=12x
Now we will be subtracting 2x from both sides of the equation
2x-2x-4=12x-2x
-4=10x
10x=-4
Dividing both sides by 10

Hence,
The value of x is
.
Assume you need x liters 10% acid, y liters 80% acid
Then 10%x + 80%y = 65%*70, and x+y = 70
I get: x = 15, y = 55
Multiply the two numbers to find the amount of the loan.
5530/1* 4/7= 22120/7= 3160
Final answer: $3,160
<h3>
Answer: (-4, 8)</h3>
=========================================================
Explanation:
The 90 degree counterclockwise rotation rule we use is

the x and y coordinates swap places, and we change the sign of the first coordinate after the swap.
After using that rotation rule, we would go from (8,4) to (-4, 8) which is the final answer.
----------------
Extra info (optional section):
Define the following three points
A = (0,0)
B = (8,4)
C = (-4,8)
Use the slope formula to find that AB and AC have slopes of 1/2 and -2 in that order.
Those slopes multiply to -1, since (1/2)*(-2) = -1. This is a property of any two perpendicular lines as long as neither line is vertical and neither is horizontal. So this is sufficient to prove that the lines are perpendicular. This further means that a 90 degree rotation has taken place.