Algebra Help ? HW ! I am completely lost !?

y = 2x + 3 is the equation of a straight line and you are required to determine if the points (-3,-3), (2,7) and (3,9) are on this line.

The points are each given as a coordinate pair of the form (x,y). Hence for (-3,-3) c = -3 and y = -3. For the point (2,7), x = 2 and y = 7.

To check if each point is a solution to the equation, pick the x value and substitute this into the equation to see if you get the required result.

Thus when x = -3, y should = -3

y =2*(-3) + 3 = -6+3 = -3. The given value of y is -3 so this point is a solution.

When x = 2 y should = 7

y = 2*2 + 3 = 7. The given value of y is 7 so this point is a solution.

When x = 3, y should = 9

y = 2*3 +3 = 9. The given value of y is 9 so this point is also a solution.

Well, in an ordered pair, x comes first, and y comes second. So in each of those three solutions, the first number is x and the second number is y. So you just need to plug them in for x and y and see which one works.

y=2x+3 is the equation. So plug in the first solution.

-3=2 (-3)+3. This equals 3. So that is not correct.

Now lets plug in the second solution.

7=2 (2)+3. This equals 7. So that one works.

Now lets plug in the third solution.

9= 2 (3)+3. This equals 9. So that, too, works.

So the two answers would be the second and third equation.

Your answers are (x,y) . (x.y) . (x.y) which

correspond to (-3,-3),(2,7), (3,9)

plug each x and y into the equation y=2x+3

ill work out the second one

ex: y=2x+3

(7)=2(2) + 3

7= 4 + 3

7=7

They work cuz each side is equal to the other

You plug in the first value from the ordered pair in for x, and the second one for y. (-3,-3) into y=2x+3 would be -3=-6+3 which simplifies to -3=-3

Since that statement is true the ordered pair (-3,-3) works.

All three answers work.

(x, y)

(2, 7)

x=2

y=7

7=2(2)+3

7=4+3

Answer is true

Plug each x value from each set into the equation and see if the outcome matches the respective y value.