Solving a system of linear equations using a graph
A system of linear equations includes two or more linear equations. The graphs of two lines will intersect at a single point if they are not parallel. Two parallel lines can also intersect if they are coincident, which means they are the same line and they intersect at every point. For two lines that are not parallel, the single point of intersection will satisfy both equations and therefore represent the solution to the system.
To find this point when the equations are given as functions, we can solve for an input value so that
In other words, we can set the formulas for the lines equal to one another, and solve for the input that satisfies the equation.
Finding a point of intersection algebraically
Find the point of intersection of the lines
and
Set
This tells us the lines intersect when the input is
We can then find the output value of the intersection point by evaluating either function at this input.
If we were asked to find the point of intersection of two distinct parallel lines, should something in the solution process alert us to the fact that there are no solutions?
Yes. After setting the two equations equal to one another, the result would be the contradiction “0 = non-zero real number”.
Look at the graph in
[link] and identify the following for the function
y- intercept
x -intercept(s)
slope
Is
parallel or perpendicular to
(or neither)?
Is
an increasing or decreasing function (or neither)?
Write a transformation description for
from the identity toolkit function
Slope -1
Neither parallel nor perpendicular
Decreasing function
Given the identity function, perform a vertical flip (over the
t -axis) and shift up 5 units.
A company sells sports helmets. The company incurs a one-time fixed cost for $250,000. Each helmet costs $120 to produce, and sells for $140.
Find the cost function,
to produce
helmets, in dollars.
Find the revenue function,
from the sales of
helmets, in dollars.
Find the break-even point, the point of intersection of the two graphs
The cost function in the sum of the fixed cost, $125,000, and the variable cost, $120 per helmet.
The revenue function is the total revenue from the sale of
helmets,
The break-even point is the point of intersection of the graph of the cost and revenue functions. To find the
x -coordinate of the coordinate pair of the point of intersection, set the two equations equal, and solve for
To find
evaluate either the revenue or the cost function at 12,500.
for the "hiking" mix, there are 1,000 pieces in the mix, containing 390.8 g of fat, and 165 g of protein. if there is the same amount of almonds as cashews, how many of each item is in the trail mix?
an object is traveling around a circle with a radius of 13 meters .if in 20 seconds a central angle of 1/7 Radian is swept out what are the linear and angular speed of the object
like this: (2)/(2-x)
the aim is to see what will not be compatible with this rational expression. If x= 0 then the fraction is undefined since we cannot divide by zero. Therefore, the domain consist of all real numbers except 2.
functions can be understood without a lot of difficulty.
Observe the following:
f(2) 2x - x
2(2)-2= 2
now observe this:
(2,f(2)) ( 2, -2)
2(-x)+2 = -2
-4+2=-2
a colony of bacteria is growing exponentially doubling in size every 100 minutes. how much minutes will it take for the colony of bacteria to triple in size
100•3=300
300=50•2^x
6=2^x
x=log_2(6)
=2.5849625
so, 300=50•2^2.5849625
and, so,
the # of bacteria will double every (100•2.5849625) =
258.49625 minutes
Thomas
158.5
This number can be developed by using algebra and logarithms.
Begin by moving log(2) to the right hand side of the equation like this:
t/100 log(2)= log(3)
step 1: divide each side by log(2)
t/100=1.58496250072
step 2: multiply each side by 100 to isolate t.
t=158.49
Dan
what is the importance knowing the graph of circular functions?
yeah, it does. why do we attempt to gain all of them one side or the other?
Melissa
how to find x:
12x = 144
notice how 12 is being multiplied by x. Therefore division is needed to isolate x
and whatever we do to one side of the equation we must do to the other.
That develops this:
x= 144/12
divide 144 by 12 to get x.
addition:
12+x= 14
subtract 12 by each side. x =2
The domain of a function is the set of all input on which the function is defined. For example all real numbers are the Domain of any Polynomial function.
Spiro
Spiro; thanks for putting it out there like that, 😁
Melissa
foci (–7,–17) and (–7,17), the absolute value of the differenceof the distances of any point from the foci is 24.
