Answer: 
Step-by-step explanation:
To find the slope of the line , we will write the equation in the form:
where:
slope
y - intercept.
To write 
in this form , we will make y the subject of the formula.
Subtract 4x from both sides
Divide through by 2
Therefore :
Answer:
600 minutes
Step-by-step explanation:
If we write both situations as an equation, we get:
y1 = 24 + 0.15x
<em>y1 </em><em>:</em><em> </em><em>total </em><em>cost </em><em>paid </em><em>in </em><em>first </em><em>plan</em>
<em>x </em><em>:</em><em> </em><em>total minutes </em><em>of </em><em>calls</em>
y2 = 0.19x
<em>y2 </em><em>:</em><em> </em><em>total </em><em>cost </em><em>in </em><em>second </em><em>plan</em>
<em>x:</em><em> </em><em>total </em><em>min</em><em>utes </em><em>of </em><em>call</em>
We are now looking for the situation where the total cost in the two plans is equal, so
y1 = y2
this gives
24 + 0.15x = 0.19x
<=> 0.04x = 24
<=> x = 600
It will take 148
hours (In decimal form its 148.66336633)
500500-200200=300300
300300÷2020=148.66336633
I'm guessing the sum is supposed to be
Split the summand into partial fractions:
If 
, then
If 
, then
This means
Consider the 
th partial sum of the series:
The sum telescopes so that
and as 
, the second term vanishes and leaves us with
