Answer:
r = 4/5
Step-by-step explanation:
Formula
Sum of an infinite geometric series = a / (1 - r)
Givens
Sum = 5*a
a = a
r = ?
Solution
5a = a/(1 - r) Divide both sides by a
5a/a = a / (a * (1 - r) The a's on the right cancel
5 = 1 / (1 - r) Multiply both sides by 1 - r
5*(1 - r) = 1*(1 - r)/(1 - r) The 1 - r s on the right cancel
5*(1 - r) = 1 Remove the brackets.
5 - 5r = 1 Subtract 5 from both sides
5-5 - 5r = 1 - 5 Combine
-5r = - 4 Divide by - 5
r = 4/5
Answer:
Step-by-step explanation:
2x + 1 + 7x= -8
~2x + 7x = 9x
9x + 1 = -8
move 1 to the other side
9x = -1 -8
9x = -9
divide
X = -1
Answer:

Step-by-step explanation:
Hi there!
<u>What we need to know:</u>
- Linear equations are typically organized in slope-intercept form:
where m is the slope and b is the y-intercept (the value of y when x is 0) - Parallel lines always have the same slopes
<u>1) Determine the slope (m)</u>

The given line has a slope of -2. Because parallel lines always have equal slopes, we know that the line parallel to this would also have a slope of -2. Plug this into
:

<u>2) Determine the y-intercept (b)</u>

Plug in the given point (2,4) to solve for b

Add 4 to both sides to isolate b

Therefore, the y-intercept of the line is 8. Plug this back into
:

I hope this helps!
It is parallel, which means that the new line should have the same slope of the given line

and the slope is the coefficient of x
so the slope = -5/4
in order to solve this problem we have to know the equation of the slop

where (x1,y1) is the point by which the new line passes through


-5(x-1)=4(y+4)
-5x +5=4y+16 (by subtracting 16 from both sides)
-5x -11= 4y (divide both sides by 4)
y=