ch7 graphing

ch.7; 7.1,

exercises:

warm ups: true or false and explain:

1. the ordered pair (1,2) is in the solution set to the equation 2x+y=4

true because if x=1 and y=2 then 2(1)+2=4 is correct.

2. the ordered pair (1,2) satisfies 2x+y=4 and 3x-y=6

false, because if x=1 and y=2 then 3(1)-2=6 is incorrect. Both equations must be satisfied for the compound statement using and to be true.

3. the ordered pair (2,3) satisfies 4x-y=5, and 4x-y=-5


false because, (2,3) does not satisfy 4x-y=-5

4(2)-3=5 8-3=5 a true statement 4(2)-3=-5 not true the answer is 5 not a -5.

4. if two distinct straight lines in the coordinate plane are not parallel, then they intersect in one disticnt place.

true.

5. the substitution method is used to eliminate a variable.

true because when we substitute one of the variable are eliminated.

6. no ordered pair satisfies y=3x-5 and y=3x+1

true because each of these lines has a slope of 3 and are parallel.

7. the equation y=3x-6 and y=2x+4 are independant.

true because, the lines are not parallel and they have differant y intercepts.

8. the equation y=2x+7 and y= 2x+8 are inconsistant.

true because, the lines are parallel and have differant y intercepts.

9. the graphs of dependant equations are the same.

true because, dependant equations have the same solution sets.

10. the graphs of a linear equation intersects at exactly one point.

true because, a system of independent equations has one point in its solution set.

that is all for now.

Marie Zajac

Bachelor of Arts Degree in Psychology with a concentration in rehabilitation counseling.