Answer:
y=x-3
Step-by-step explanation:
Graph y=x-5 and the point (1,-2). You want your slope to be the same for the lines to be parallel. The slope in the given equation is 1/1. Type into a graphing calculator y=x- and pick a number greater than negative five since the point (1,-2) is above the given line. Guess and checking reveals -3 to be the correct answer. Therefore, your answer is y=x-3.
Remember that the general decay equation is:
where
is the amount after a time
is the initial amount
is the the decay percent in decimal form
The first ting we are going to do is find
by dividing our <span>decay rate of 25% by 100%: </span>
.
We also know from our problem that
. Lets replace
and
in our formula:
We know now that our decay rate is 0.75, and since 0.75<1, we can conclude that
this situation represents exponential decay.
Now, to find the initial amount, we are going to solve our equation for
:
Notice that
will depend on the number of ours
. <span />
7:
Parallel lines have the same slope
y = -3x + b
Plug in the x and y values from the point
5 = -3(-4) + b
5 = 12 + b
-7 = b
Answer to 7: y = -3x -7
8:
Perpendicular lines have opposite reciprocal slopes
y = -2x + b
Plug in x and y from the point
-6 = -2(7) + b
-6 = -14 + b
8 = b
Answer to 8: y = -2x + 8
Substitute (-1)3-(-1)+(-1)0
multiply (-3)+1+0
simplify. -2
Final Answer: -2
