Try our Free Online Math Solver!

Linear Mathematics Review 1
1. The straight line goes through the points (3, 2) and
(4, 1). Find the slope of the line .
According to the formula we have
2. Write a pointslope equation for the line from Problem
1.
If we know the slope m and a point on the
straight line we can write an equation in the point slope form as.
If we use e.g. the point (3,2) then we can write
3. Write the slope intercept equation for the line from
Problem 1.
We will solve the equation we got in the previous problem for y.
4. Write an equation of the line parallel to the line from
Problem 1 and going through the
point (1,3).
Parallel lines have equal slopes and therefore we can write an equation of this
parallel line in the pointslope form
Solving for y we get an equation in the
slope intercept form
5. Write an equation of the line perpendicular to the line
from Problem 1 and going
through the point (1,3).
The slopes of perpendicular lines are negative reciprocals
and therefore the slope of the perpendicular
line is 7/3 and its equation in the pointslope form
Solving for y we get an equation in the
slopeintercept form
6. Graph the lines from Problems 1 and 5 in the same coordinate system .
7. Find the point of intersection of the lines from
Problems 1 and 5.
We have to solve the system of equations
Because the left parts are equal so are the right parts.
Multiplying both parts
by the common denominator, 21, we get
After we plug this value of x into the firs
equation we get
8. The straight line has the xintercept 2 and the
yintercept 3. Write an equation of the
line. We use the formula where a and b are
the xintercept and the yintercept, respectively. In our case
9. If the price of a CDplayer is $40 the demand is 4000.
If the price of the same
CD player is $60 the demand is 3000. Assuming that the demand is a linear
function
of the price find the demand if the price is $55.
First we need the slopeintercept equation of the line through the points (40, 4000) and (60, 3000). The slope of the line is Using for example the first point we can write an equation of the line in the pointslope
form . From here, If then.
10. A small company produces dolls. The permanent monthly
expenses are $6000 and the
Cost of producing a doll is $3. If the dolls sell for $10 each what is the
breakeven
point?
The cost of producing x dolls is The corresponding revenue is To find the breakeven point we have to solve the equation or We have
Prev  Next 