# 4.7 Graphs of linear inequalities  (Page 6/10)

 Page 6 / 10

$x+y=-4$

Answers will vary.

$y=3x+1$

$y=\text{−}x-1$

Answers will vary.

## Graphing Linear Equations

Recognize the Relation Between the Solutions of an Equation and its Graph

In the following exercises, for each ordered pair, decide:

1. Is the ordered pair a solution to the equation?
2. Is the point on the line?

$y=\text{−}x+4$

$\left(0,4\right)$ $\left(-1,3\right)$

$\left(2,2\right)$ $\left(-2,6\right)$

$y=\frac{2}{3}x-1$

$\left(0,-1\right)$ (3, 1)

$\left(-3,-3\right)$ (6, 4)

yes; yes  yes; no

Graph a Linear Equation by Plotting Points

In the following exercises, graph by plotting points.

$y=4x-3$

$y=-3x$

$y=\frac{1}{2}x+3$

$x-y=6$

$2x+y=7$

$3x-2y=6$

Graph Vertical and Horizontal lines

In the following exercises, graph each equation.

$y=-2$

$x=3$

In the following exercises, graph each pair of equations in the same rectangular coordinate system.

$y=-2x$ and $y=-2$

$y=\frac{4}{3}x$ and $y=\frac{4}{3}$

## Graphing with Intercepts

Identify the x - and y -Intercepts on a Graph

In the following exercises, find the x - and y -intercepts.

$\left(3,0\right),\left(0,3\right)$

Find the x - and y -Intercepts from an Equation of a Line

In the following exercises, find the intercepts of each equation.

$x+y=5$

$x-y=-1$

$\left(-1,0\right),\left(0,1\right)$

$x+2y=6$

$2x+3y=12$

$\left(6,0\right),\left(0,4\right)$

$y=\frac{3}{4}x-12$

$y=3x$

$\left(0,0\right)$

Graph a Line Using the Intercepts

In the following exercises, graph using the intercepts.

$\text{−}x+3y=3$

$x+y=-2$

$x-y=4$

$2x-y=5$

$2x-4y=8$

$y=2x$

## Slope of a Line

Use Geoboards to Model Slope

In the following exercises, find the slope modeled on each geoboard.

$\frac{4}{3}$

$-\frac{2}{3}$

In the following exercises, model each slope. Draw a picture to show your results.

$\frac{1}{3}$

$\frac{3}{2}$

$-\frac{2}{3}$

$-\frac{1}{2}$

Use $m=\frac{\text{rise}}{\text{run}}$ to find the Slope of a Line from its Graph

In the following exercises, find the slope of each line shown.

1

$-\frac{1}{2}$

Find the Slope of Horizontal and Vertical Lines

In the following exercises, find the slope of each line.

$y=2$

$x=5$

undefined

$x=-3$

$y=-1$

0

Use the Slope Formula to find the Slope of a Line between Two Points

In the following exercises, use the slope formula to find the slope of the line between each pair of points.

$\left(-1,-1\right),\left(0,5\right)$

$\left(3,5\right),\left(4,-1\right)$

$-6$

$\left(-5,-2\right),\left(3,2\right)$

$\left(2,1\right),\left(4,6\right)$

$\frac{5}{2}$

Graph a Line Given a Point and the Slope

In the following exercises, graph each line with the given point and slope.

$\left(2,-2\right)$ ; $m=\frac{5}{2}$

$\left(-3,4\right)$ ; $m=-\frac{1}{3}$

x -intercept $-4$ ; $m=3$

y -intercept 1; $m=-\frac{3}{4}$

Solve Slope Applications

In the following exercises, solve these slope applications.

The roof pictured below has a rise of 10 feet and a run of 15 feet. What is its slope?

A mountain road rises 50 feet for a 500-foot run. What is its slope?

$\frac{1}{10}$

## Intercept Form of an Equation of a Line

Recognize the Relation Between the Graph and the Slope–Intercept Form of an Equation of a Line

In the following exercises, use the graph to find the slope and y -intercept of each line. Compare the values to the equation $y=mx+b$ .

$y=4x-1$

$y=-\frac{2}{3}x+4$

slope $m=-\frac{2}{3}$ and y -intercept $\left(0,4\right)$

Identify the Slope and y-Intercept from an Equation of a Line

In the following exercises, identify the slope and y -intercept of each line.

$y=-4x+9$

$y=\frac{5}{3}x-6$

$\frac{5}{3};\left(0,-6\right)$

$5x+y=10$

$4x-5y=8$

$\frac{4}{5};\left(0,-\frac{8}{5}\right)$

Graph a Line Using Its Slope and Intercept

In the following exercises, graph the line of each equation using its slope and y -intercept.

$y=2x+3$

$y=\text{−}x-1$

$y=-\frac{2}{5}x+3$

$4x-3y=12$

In the following exercises, determine the most convenient method to graph each line.

#### Questions & Answers

4x+7y=29,x+3y=11 substitute method of linear equation
Srinu Reply
substitute method of linear equation
Srinu
Solve one equation for one variable. Using the 2nd equation, x=11-3y. Substitute that for x in first equation. this will find y. then use the value for y to find the value for x.
bruce
I want to learn
Elizebeth
help
Elizebeth
I want to learn. Please teach me?
Wayne
1) Use any equation, and solve for any of the variables. Since the coefficient of x (the number in front of the x) in the second equation is 1 (it actually isn't shown, but 1 * x = x), use that equation. Subtract 3y from both sides (this isolates the x on the left side of the equal sign).
bruce
2) This results in x=11-3y. x is note in terms of y. Use that as the value of x and substitute for all x in the first equation. The first equation becomes 4(11-3y)+7y =29. Note that the only variable left in the first equation is the y. If you have multiple variable, then something is wrong.
bruce
3) Distribute (multiply) the 4 across 11-3y to get 44-12y. Add this to the 7y. So, the equation is now 44-5y=29.
bruce
4) Solve 44-5y=29 for y. Isolate the y by subtracting 44 from birth sides, resulting in -5y=-15. Now, divide birth sides by -5 (since you have -5y). This results in y=3. You now have the value of one variable.
bruce
5) The last step is to take the value of y from Step 4) and substitute into the 2nd equation. Therefore: x+3y=11 becomes x+3(3)=11. Then multiplying, x+9=11. Finally, solve for x by subtracting 9 from both sides. Therefore, x=2.
bruce
6) The ordered pair of (2, 3) is the proposed solution. To check, substitute those values into either equation. If the result is true, then the solution is correct. 4(2)+7(3)=8+21=29. TRUE! Finished.
bruce
At 1:30 Marlon left his house to go to the beach, a distance of 5.625 miles. He rose his skateboard until 2:15, and then walked the rest of the way. He arrived at the beach at 3:00. Marlon's speed on his skateboard is 1.5 times his walking speed. Find his speed when skateboarding and when walking.
Andrew Reply
divide 3x⁴-4x³-3x-1 by x-3
Ritik Reply
how to multiply the monomial
Ceny Reply
Two sisters like to compete on their bike rides. Tamara can go 4 mph faster than her sister, Samantha. If it takes Samantha 1 hours longer than Tamara to go 80 miles, how fast can Samantha ride her bike? Got questions? Get instant answers now!
Seera Reply
how do u solve that question
Seera
Two sisters like to compete on their bike rides. Tamara can go 4 mph faster than her sister, Samantha. If it takes Samantha 1 hours longer than Tamara to go 80 miles, how fast can Samantha ride her bike?
Seera
Speed=distance ÷ time
Tremayne
x-3y =1; 3x-2y+4=0 graph
Juned Reply
Brandon has a cup of quarters and dimes with a total of 5.55\$. The number of quarters is five less than three times the number of dimes
ashley Reply
app is wrong how can 350 be divisible by 3.
Raheem Reply
June needs 48 gallons of punch for a party and has two different coolers to carry it in. The bigger cooler is five times as large as the smaller cooler. How many gallons can each cooler hold?
Susanna Reply
Susanna if the first cooler holds five times the gallons then the other cooler. The big cooler holda 40 gallons and the 2nd will hold 8 gallons is that correct?
Georgie
@Susanna that person is correct if you divide 40 by 8 you can see it's 5 it's simple
Ashley
@Geogie my bad that was meant for u
Ashley
Hi everyone, I'm glad to be connected with you all. from France.
Lorris Reply
I'm getting "math processing error" on math problems. Anyone know why?
Ray Reply
Can you all help me I don't get any of this
Jade Reply
4^×=9
Alberto Reply
Did anyone else have trouble getting in quiz link for linear inequalities?
Sireka Reply
operation of trinomial
Justin Reply

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