The first problem, all you need to do is combine like terms then isolate the n:
4n-2n=4
~subtract 2n from 4n (2n)
2n=4
~then divide both sides of the equation by 2 to isolate the n
n=4
The second problem follows the same steps of combining like terms and isolating the variable. Here, you'll have to combine 2 like terms:
-12=2+5v+2v
~first combine the variables which is just 5v+2v which is 7v
-12=2+7v
~then subtract 2 from both sides to isolate the 7v
-14=7v
~then divide both sides by 7 to isolate the v and get your answer
-2=v
Hope that helped!
Answer:
I think number 2 is the answer, but 4 could be the answer.
Step-by-step explanation:
x²+4x=8
rearrange
x² + 4x - 8 = 0
half of 4 is 2
so
x² + 4x + 2² - 2² - 8 = 0
do x² + 4x + 2²
multiplies to give 4 adds to give 4
2+ 2
(x + 2)²
(x + 2)² - 2² - 8
(x + 2)² - 4 - 8
(x + 2)² - 12
(x + 2 + √12) (x + 2 - √12)
√12 = √4 * √3 = 2 √3
(x + 2 + 2√3) (x + 2 - 2√3)
The rule is "whatever the input is, multiply it by 5, then subtract 2"
For example, if the input is 4 then 4*5 = 20 and 20-2 = 18
So in short, the input 4 leads to the output 18 as shown in the top row of the diagram.
The answer is the box on the bottom row, right hand side where it says "x 5" and "-2" in the two bubbles.
