Which point is in the solution set for y < x+2? Explain your answer. A. (-2, 0) because when you graph y < x+2, it is the x-intercept of the boundary line. B. (1, 4) because when you graph y < x+2, it is a point that lies above the boundary line. C. (2, 1) because when you graph y < x+2, it is a point that lies below the boundary line. D. (0, 2) because when you graph y < x+2, it is a point on the boundary line.
@Vocaloid
any attempts so far? try plugging in the coordinates into y < x + 2 to see which one is true
the answer is A or C
if you plug in (-2,0) into the equation y < x + 2 is it true or false?
true
(-2,0) means x = -2 and y = 0 0 < -2 + 2 is this true or false?
sorry false my mistake
good so it can't be A C is the only one that works
A system of inequalities is shown: y ≤ x + 6 y ≥ 9x − 9 Which point is in the solution set of the system of inequalities shown? Explain your answer. A. (3, 2) because it lies above the boundary line y=9x−9. B. (-2, 2) because it lies above the boundary line y=9x−9 and below the boundary line y=x+6. C. (3, 10) because it lies below the boundary line y=9x−9 and above the boundary line y=x+6. D. (-1, 7) because it lies below the boundary line y=x+6.
try plugging in each answer choice and see which one makes both inequalities true
the answer is C
if you plug in (3,10) into y ≥ 9x − 9 is the inequality true or false?
false
good so the answer is not C, keep trying with the other choices
now it's either B or D
a OR c fit it
we have just concluded that it is not C please do the calculations and see which answer choice makes the inequality true.
B if i'm not mistaken
good, B
A point (x, y) is the solution for the inequality y ≥ 2x + 1. Which ordered pair has a y value that is less than or equal to 1 and satisfies the inequality shown? A. (3, 8) B. (1, 1) C. (0, 1) D. (2, 3)
the correct answer will satisfy two conditions: 1. the y-coordinate is less than or equal to 1 and 2. y ≥ 2x + 1 will be true which answer choice satisfies both conditions?
D.
notice how for point (2,3) the y- coordinate is 3 which is greater than 1 so this cannot be our solution.
B
when you plug in (1,1) into y ≥ 2x + 1 is the inequality true or false?
FALSE
good so B cannot be the solution either
C
well done
(x, y) is the point of intersection of the boundary lines of the system of inequalities: y ≥ −3x + 5 y ≤ x + 1 Select the graph that represents a system of inequalities that includes the same point of intersection (x, y) in its solution set. A. https://d3upxwx9bggvi1.cloudfront.net/img/questions/arei12_1_222a.png B. https://d3upxwx9bggvi1.cloudfront.net/img/questions/arei12_1_222d.png C. https://d3upxwx9bggvi1.cloudfront.net/img/questions/arei12_1_222b.png D. https://d3upxwx9bggvi1.cloudfront.net/img/questions/arei12_1_222c.png
I don't know if you would see it
hm. none of these graphs look right based on the equation, are those equations correct? :S
YES it's just in black form i don't know why they're like that
oh I think I know what they want you to do now ok, so let's solve y ≥ −3x + 5 y ≤ x + 1 for the point of intersection
cause when i solved it, i didn't look right with the equations
LIKE THEY DON'T MATCH
since they're both equal to y you can set -3x + 5 = x + 1 and solve for x
x = 1
good, now we plug x into one of the y-equations y = x + 1 which means y = 1 + 1 = 2 so (1,2) is the solution now look at each of the four graphs to see which one contains (1,2) within either the red or the blue regions
the answer is C
|dw:1523638152180:dw|
so C isn't quite it, keep trying with the other graphs
A
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|dw:1523638285942:dw|
notice how the point (1,2) is not inside either the blue or red regions make sure the point (1,2) is inside the blue or red regions, that is a requirement to be the solultion
ok D
good
The graph shown represents a system of inequalities. https://d3upxwx9bggvi1.cloudfront.net/img/questions/arei12_1_245.png Which system of inequalities is represented by the graph shown? A. y > 2x − 5 y > −7x + 2 B. y < 2x − 5 y < −7x + 2 C. y < 2x − 5 y > −7x + 2 D. y > 2x − 5 y < −7x + 2
first check the graph and look at the red line pretend it's just a regular line not a dotted line, what would be the equation in y = mx + b form for the red line?
the answer i chose is D
well done
THANK YOU FOR ALL YOUR HELP, I ALWAYS APPRECIATE IT
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