Answer: (2,2)
Step-by-step explanation:
I'm going to use substitution to solve this:
First, I use the second equation to solve for y in terms of x.
2x - y = 2
-y = 2 - 2x
y = 2x - 2
Then, I plug the value for y into the first equation:
2x + 4y = 12
2x + 4(2x - 2) = 12
2x + 8x - 8 = 12
10x - 8 = 12
10x = 20
x = 2
Now that we have x, we can plug it into either equation (I used the first) to get the value for y:
2x + 4y = 12
2(2) + 4y = 12
4 + 4y = 12
4y = 8
y = 2
We get the point (2,2) as a solution.
Note: This is the point where both lines intersect.
5 7/8 is 47/8
Because,
You multiply 5 and 8 and then add 7, then you keep the denominator.
Answer:
Step-by-step explanation:
Answer: 42 -(-6)= 48
Step-by-step explanation:
a negative - a negative will always equal a positive
:)
Answer:
an = 115 + (n - 1) (-6)
a25 = - 29
Step-by-step explanation:
We use the definition for the nth term of an arithmetic sequence:
an = a1 + (n - 1) d
a5 = 91 = a1 + (5 - 1) d
91 = a1 + 4 d
a20 = 1 = a1 + (20 - 1) d = a1 + 19 d
1 = a1 + 19 d
now we subtract term by term one expression from the other
90 = 4 d - 19 d
90 = - 15 d
divide both sides by -15 to isolate d
d = 90 / (-15) = -6
Now we can calculate what a1 is using for example:
1 = a1 + 19 d
1 = a1 - 114
add 114 to both sides:
115 = a1
Then our general expression for the sequence is:
an = 115 + (n - 1) (-6)
We can now use it to calculate the value of a25:
a25 = 115 + (24) * (-6) = -29
