3x-4y=18
+3x +3x
-----------------
-4y=3x+18
÷-4 ÷-4
----------------
y=-3/4x-6
x+3y=-7
-x -x
------------
3y=-x-7
÷3 ÷3
--------------
y=-x-7/3
I think but not sure :)
2. The total number of ski trails is 12. That's how many numbers there are in the box.
3. The difference in length between the longest ski trail and the shortest ski trail is the biggest number minus the smallest number in the box. 3 1/8 minus 1 3/8 is 1 and 3/4. So the answer is 1.75 or 1 3/4, whichever one works.
4. There are 3 trails that are 2 7/8 miles long. so You do 2 7/8 times three or 2 7/8 plus 2 7/8 plus 2 7/8. That equals 8 19/40 which is the answer. Ti add them together first turn them into mixed numbers. 2 7/8 is the same as 23/8. 8x3=24. 23x3=69. 69/24 is the same is 8 19/40 through further simplification.
5. 3 1/8 plus 1 3/8 is 4 1/2 or 4.5
6. The shortest ski trail is 1 3/8. 1 3/8 times 3 is 4.125. 4 is greater than 3 which means Sam is automatically right.
Two consecutive odd number have the form: 2n+1; 2n+3.
We have:
(2n+1)(2n+3)=399
=> 4x^2+8x+3=399
=> 4x^2+8x-396=0
=> 4(x+11)(x-9)=0
=> x=-11; x=9
Answer:
work is shown and pictured
<h3>
Answer: (x+1)(x+3)</h3>
===================================================
Explanation:
Let's assume it factors into (x+a)(x+b)
The goal is to find the two numbers a and b.
FOIL out (x+a)(x+b) to get x^2+(a+b)x+ab
Note how a+b is the middle term and ab is the last term.
In the original expression, 4 is the middle term and 3 is the last term.
So we need to find two numbers that
There are two ways to multiply to 3 and they are
- 1 times 3 = 3
- -1 times -3 = -3
But only the first way has the factors add to 4. So that means a = 1 and b = 3.
Therefore (x+a)(x+b) = (x+1)(x+3)
And x^2+4x+3 = (x+1)(x+3)