The answer is This answer and this answer is B
Answer:
n=21
Step-by-step explanation:
We must find n.
Remember PEMDAS. First we must do the Parentheses. Lets do distributive property by multiplying a number that is immediately outside the parentheses with each number inside the parentheses. Lets do this one side at a time.
First lets do 5(n - 7). We get 5n - 35
Now 2(n + 14) is 2n + 28
Okay...... now we have 
Now lets do OPPOSITES!!!! We must do the opposite of each thing to both sides.
The opposite of -35 is positive 35. Lets add 35 to both sides. We get:

Now lets do the opposite of 2n which is -2n

this is looking quite nice isnt it..........
The opposite of 3 times n is 3 DIVIDED BY n. So lets divide both sides by 3

amazing.......
Solve each system using a matrix
7x+2y=5
13x+14y=-1Solve each system using a matrix
7x+2y=5
13x+14y=-1
Answer:
the answe is b (1,7)
Step-by-step explanation:
Solve the equation for x by finding a, b, and c of the quadratic then applying the quadratic formula.
x
=
7,1