Answer:

Step-by-step explanation:
1) Add 6 to both sides.

2) Simplify 21 + 6 to 27.

3) Divide both sides by 9.

4) Simplify 27/9 to 3.

<u>Therefor</u><u>,</u><u> </u><u>the</u><u> </u><u>answer</u><u> </u><u>is</u><u> </u><u>option</u><u> </u><u>B</u><u>.</u><u> </u><u>x</u><u> </u><u>></u><u> </u><u>3</u>.
Please: Use "^" to denote exponentiation: <span>2x^2 + 8x - 12 = 0
Reduce this by div. every term by 2: </span><span>x^2 + 4x - 6 = 0
Here a=1, b=4 and c = -6. Square half of b, obtaining (4/2)^2 = 4, and add, and then subtract, this 4 to x^2 + 4x - 6:
</span> x^2 + 4x +4 - 4 - 6 = 0. Rewrite the square as (x+2)^2, obtaining new equation
(x+2)^2 = 10. Take the sqrt of both sides: x+2 = plus or minus sqrt(10).
Finally, solve for x: x = -2 plus or minus sqrt(10).
We are given statement : 3 more than a number then divided the result by 8.
We need to write an algebraic expression for it.
Let us assume unknown number be n.
3 more than n = (n+3).
Now, we need to divide that result (n+3) by 8.
So, we would get (n+3) divided by 8 =
.
<h3>Therefore, final expression is

</h3>
Answer: 54 mph
Step-by-step explanation:
d-the distance
s+9 - the speed to the conference
d=6*(s+9)
s- is the speed on the way back home
d=7*s
so 6*(s+9)=7*s
6s+54=7s
-6s -6s
54= 7s-6s
s=54 mph
Answer: 1. X+2
2. 6x-3
3. -2x-1
4. 9x5
Step-by-step explanation:
1. X+4-3+1 There is only one variable, so you don’t need to worry about that. Just do all of the numerical operations. 4-3+1= 2. So it would be x+2
2. X-5+5x+2. Again, do the numerical operations first. -5+2=-3. X+5x=6x. So it would be 6x-3.
3. 2x+7-4x-8. 7-8=-1. 2x-4x=-2x. So it would be -2x-1.
4. (4+3)x+2x-5. Do the operation in the parenthesis first. Then it would be (7)x or just 7x+2x-5. Simplify to 9x-5.