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HELP PLEASE 32,34,35

HELP PLEASE 32,34,35-example-1

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Answer:

32) (x, y) = (2, 4)

34) (x, y) = (-2, 3)

35) (x, y) = (1, 2)

Explanation:

32) It can be helpful to remember that "intercept form" is ...

... x/(x-intercept) +y/(y-intercept) = 1

That is, if you divide each equation by the constant on the right and express the x- and y-coefficients as denominators, then those denominators are the x- and y-intercepts of the line. Knowing those can simplify graphing.

The first equation can be rewritten as ...

... x/(-2) +y/2 = 1 . . . . . . intercepts are (-2, 0) and (0, 2)

The second equation can be rewritten as ...

... x/6 +y/6 = 1 . . . . . . . intercepts are (6, 0) and (0, 6)

Then the two lines can be graphed as in the attachment, and the solution (point of intersection) found to be (x, y) = (2, 4).

34) When you use "substitution", you use an expression for a variable in place of that variable. Here, y already has an expression written for it:

... y = x + 5

Substitute that expression for y in the other equation:

... 3x + (x+5) = -3 . . . . . . . substitute x+5 for y

... 4x = -8 . . . . . . . . . . . . . simplify, subtract 5

... x = -2 . . . . . . . . . . . . . . divide by the x-coefficient

... y = x+5 = -2+5 = 3

The solution is (x, y) = (-2, 3).

35) The y-coefficients match, so it is convenient to subtract one equation from the other to eliminate the y-variable. Here, the second equation has the smallest x-coefficient, so it will work well to subtract the second equation.

... (3x -2y) -(-2x -2y) = (-1) -(-6)

... 5x = 5 . . . . simplify. The y-variable has been eliminated.

... x = 1 . . . . . . divide by the coefficient of x

... 3(1) -2y = -1 . . . . substitute for x in the first equation

... -2y = -4 . . . . . . . subtract 3

... y = 2 . . . . . . . . . divide by the coefficient of y

The solution is (x, y) = (1, 2).

HELP PLEASE 32,34,35-example-1
User Vitalii Gozhenko
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7.3k points

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